diff --git a/admin/class-admin-settings.php b/admin/class-admin-settings.php
index 4e4aa18..ac3bb49 100644
--- a/admin/class-admin-settings.php
+++ b/admin/class-admin-settings.php
@@ -122,12 +122,12 @@ private function render_help_section() {
 					<tr>
 						<td><code>teacher_mode</code></td>
 						<td><code>0</code></td>
-						<td><?php esc_html_e( 'When enabled, the content loads with teacher mode active.', 'exelearning' ); ?></td>
+						<td><?php esc_html_e( 'When enabled, the teacher layer selector is offered so viewers can reveal teacher content.', 'exelearning' ); ?></td>
 					</tr>
 					<tr>
 						<td><code>teacher_mode_visible</code></td>
 						<td><code>1</code></td>
-						<td><?php esc_html_e( 'Whether the teacher-mode toggle button is shown.', 'exelearning' ); ?></td>
+						<td><?php esc_html_e( 'If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.', 'exelearning' ); ?></td>
 					</tr>
 					<tr>
 						<td><code>show_download</code></td>
diff --git a/assets/js/elp-upload.js b/assets/js/elp-upload.js
index 6919d67..e499db7 100644
--- a/assets/js/elp-upload.js
+++ b/assets/js/elp-upload.js
@@ -234,7 +234,7 @@
             },
             teacherModeVisible: {
                 type: 'boolean',
-                default: true,
+                default: false,
             },
             showDownload: {
                 type: 'boolean',
@@ -344,7 +344,7 @@
                     previewUrl: undefined,
                     title: undefined,
                     hasPreview: false,
-                    teacherModeVisible: true,
+                    teacherModeVisible: false,
                 });
             }
 
@@ -410,8 +410,9 @@
                             step: 10,
                         }),
                         el( ToggleControl, {
-                            label: __( 'Show Teacher Mode toggler', 'exelearning' ),
-                            checked: attributes.teacherModeVisible !== false,
+                            label: __( 'Show teacher layer selector', 'exelearning' ),
+                            help: __( 'If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.', 'exelearning' ),
+                            checked: attributes.teacherModeVisible === true,
                             onChange: function( value ) {
                                 setAttributes( { teacherModeVisible: value } );
                             },
diff --git a/docs/SHORTCODES.md b/docs/SHORTCODES.md
index 05f31d7..cee3c53 100644
--- a/docs/SHORTCODES.md
+++ b/docs/SHORTCODES.md
@@ -30,26 +30,31 @@ Library, e.g. in the URL `…/upload.php?item=123`).
 |-----------|------|---------|----------------|-------------|
 | `id` | int | `0` | Any attachment ID | **Required.** Media Library attachment ID of the `.elpx` package. Nothing renders without a valid ID. |
 | `height` | int | `600` | Pixels | Height of the preview iframe (and of the screenshot poster) in pixels. |
-| `teacher_mode` | bool | `0` | `0`/`1`, `false`/`true`, `no`/`yes` | When enabled, the embedded content loads with **teacher mode active**, so teacher-only content is shown from the start. |
-| `teacher_mode_visible` | bool | `1` | `0`/`1`, `false`/`true`, `no`/`yes` | Controls whether the teacher-mode **toggle button** is visible inside the embed. Set to `0` to hide it. |
+| `teacher_mode` | bool | `0` | `0`/`1`, `false`/`true`, `no`/`yes` | When enabled, the **teacher layer selector** is offered in the embed so viewers can reveal teacher-only content. It no longer auto-reveals on load — the viewer turns it on. |
+| `teacher_mode_visible` | bool | `0` | `0`/`1`, `false`/`true`, `no`/`yes` | Controls whether the **teacher layer selector** is available inside the embed. Off by default; set to `1` to make it available. |
 | `show_download` | bool | `0` | `0`/`1`, `false`/`true`, `no`/`yes` | When enabled, renders a multi-format download button in the toolbar. |
 | `download_formats` | string | *(empty → all)* | Comma-separated list of `elpx`, `html5`, `scorm12`, `ims`, `epub3` | Restricts the download button to the listed formats. Empty means all available formats. Only applies when `show_download` is enabled. |
 | `screenshot` | string | `no` | `no`, `poster`, `only` | Controls whether the package screenshot is shown. See [Screenshots](#screenshots). |
 
 ### Teacher mode
 
-eXeLearning packages can mark content as *teacher-only*. The embedded viewer
-ships a toggle that switches teacher mode on and off; the two attributes above
-control it independently:
+eXeLearning packages can mark content as *teacher-only*. Exported packages hide
+that content by default and expose an in-page **teacher layer selector** to
+reveal it through the `?exe-teacher=1` URL parameter. The plugin appends that
+parameter to the embed instead of injecting any CSS or JavaScript into the
+package:
 
-- `teacher_mode` decides the **initial state** (off by default).
-- `teacher_mode_visible` decides whether the **toggle button** is shown.
+- `teacher_mode_visible` (default `0`) decides whether the **selector is
+  available** in the embed. It is hidden by default; set it to `1` to make it
+  available.
+- `teacher_mode` (default `0`), when enabled, also makes the selector available.
+  It no longer auto-reveals teacher content on load — the selector is shown but
+  stays off until the viewer turns it on.
 
-They compose freely. For example, to always present teacher content and hide the
-toggle so visitors cannot switch it off:
+For example, to offer the selector explicitly:
 
 ```text
-[exelearning id="123" teacher_mode="1" teacher_mode_visible="0"]
+[exelearning id="123" teacher_mode_visible="1"]
 ```
 
 ### Screenshots
@@ -81,16 +86,17 @@ Custom height:
 [exelearning id="123" height="800"]
 ```
 
-Activate teacher mode on load:
+Offer the teacher layer selector (hidden by default):
 
 ```text
-[exelearning id="123" teacher_mode="1"]
+[exelearning id="123" teacher_mode_visible="1"]
 ```
 
-Hide the teacher-mode toggle:
+The selector is hidden unless you enable it, so a bare embed keeps teacher-only
+content hidden:
 
 ```text
-[exelearning id="123" teacher_mode_visible="0"]
+[exelearning id="123"]
 ```
 
 Show a download button limited to specific formats:
diff --git a/includes/class-elp-upload-block.php b/includes/class-elp-upload-block.php
index a5daa56..00822f6 100644
--- a/includes/class-elp-upload-block.php
+++ b/includes/class-elp-upload-block.php
@@ -122,7 +122,7 @@ public function register_block() {
 					),
 					'teacherModeVisible' => array(
 						'type'    => 'boolean',
-						'default' => true,
+						'default' => false,
 					),
 					'showDownload'       => array(
 						'type'    => 'boolean',
@@ -189,7 +189,7 @@ private function prepare_block_render_data( $attributes ) {
 			'extracted_dir'        => get_post_meta( $attachment_id, '_exelearning_extracted', true ),
 			'has_preview'          => get_post_meta( $attachment_id, '_exelearning_has_preview', true ),
 			'height'               => isset( $attributes['height'] ) ? absint( $attributes['height'] ) : 600,
-			'teacher_mode_visible' => ! isset( $attributes['teacherModeVisible'] ) || (bool) $attributes['teacherModeVisible'],
+			'teacher_mode_visible' => isset( $attributes['teacherModeVisible'] ) && (bool) $attributes['teacherModeVisible'],
 			'show_download'        => isset( $attributes['showDownload'] ) && (bool) $attributes['showDownload'],
 			'download_formats'     => isset( $attributes['downloadFormats'] )
 				? ExeLearning_Download_Formats::sanitize( $attributes['downloadFormats'] )
@@ -220,7 +220,17 @@ private function maybe_render_download_button( $data ) {
 	 * @return string Escaped preview URL.
 	 */
 	private function build_preview_url( $data ) {
-		return esc_url( ExeLearning_Content_Proxy::get_proxy_url( $data['extracted_dir'] ) );
+		$url = ExeLearning_Content_Proxy::get_proxy_url( $data['extracted_dir'] );
+
+		// eXeLearning core hides teacher-only content by default and exposes an in-page
+		// "teacher layer" selector via ?exe-teacher=1 (shown but off until the viewer
+		// turns it on). No host-side CSS/JS injection is needed — opt in by carrying the
+		// parameter on the iframe src when this block should offer the selector.
+		if ( ! empty( $data['teacher_mode_visible'] ) ) {
+			$url .= ( false === strpos( $url, '?' ) ? '?' : '&' ) . 'exe-teacher=1';
+		}
+
+		return esc_url( $url );
 	}
 
 	/**
@@ -287,25 +297,6 @@ private function render_block_preview( $data, $download_html ) {
 			esc_attr( get_the_title( $data['attachment_id'] ) )
 		);
 
-		if ( ! $data['teacher_mode_visible'] ) {
-			$html .= $this->teacher_mode_hide_script( $data['container_id'] );
-		}
-
 		return $html;
 	}
-
-	/**
-	 * Inline script that hides the teacher-mode toggler inside the preview
-	 * iframe. The iframe is same-origin, so we inject a small stylesheet into
-	 * its document on load.
-	 *
-	 * @param string $container_id Wrapper element id.
-	 * @return string Script HTML.
-	 */
-	private function teacher_mode_hide_script( $container_id ) {
-		return sprintf(
-			'<script>(function(){var c=document.getElementById("%1$s");if(!c)return;var f=c.querySelector("iframe");if(!f)return;var css="#teacher-mode-toggler-wrapper { visibility: hidden !important; }";var inject=function(){try{if(!f.contentDocument)return;var d=f.contentDocument;if(d.getElementById("exelearning-teacher-mode-style"))return;var st=d.createElement("style");st.id="exelearning-teacher-mode-style";st.textContent=css;(d.head||d.documentElement).appendChild(st);}catch(e){}};f.addEventListener("load",inject);inject();})();</script>',
-			esc_js( $container_id )
-		);
-	}
 }
diff --git a/languages/exelearning-ca-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-ca-4cf813b039eac98ce62f176afa8fc8fe.json
index d1df3b1..6c6262d 100644
--- a/languages/exelearning-ca-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-ca-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Aquest \u00e9s un fitxer font d'eXeLearning v2. El contingut es mostrar\u00e0 al frontend si hi ha HTML exportat disponible."
             ],
-            "Show Teacher Mode toggler": [
-                "Mostra el commutador de Mode Professor"
+            "Show teacher layer selector": [
+                "Mostrar el selector de capa docent"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Si es desactiva, el selector de capa docent s'ocultar\u00e0 al contingut eXeLearning incrustat."
             ],
             "More download formats": [
                 "M\u00e9s formats de baixada"
diff --git a/languages/exelearning-ca.mo b/languages/exelearning-ca.mo
index be66f39..51a3084 100644
Binary files a/languages/exelearning-ca.mo and b/languages/exelearning-ca.mo differ
diff --git a/languages/exelearning-ca.po b/languages/exelearning-ca.po
index 6b8edc9..8fcc41e 100644
--- a/languages/exelearning-ca.po
+++ b/languages/exelearning-ca.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "La còpia del fitxer sembla estar truncada."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Mostra el commutador de Mode Professor"
+msgid "Show teacher layer selector"
+msgstr "Mostrar el selector de capa docent"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Alçada de la previsualització, en píxels."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Quan s'activa, el contingut es carrega amb el mode docent actiu."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Quan s'activa, s'ofereix el selector de capa docent perquè qui el vegi pugui mostrar el contingut docent."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Si es mostra el botó per commutar el mode docent."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Si es desactiva, el selector de capa docent s'ocultarà al contingut eXeLearning incrustat."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-ca_valencia-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-ca_valencia-4cf813b039eac98ce62f176afa8fc8fe.json
index efe3822..9bcbd8d 100644
--- a/languages/exelearning-ca_valencia-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-ca_valencia-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Este \u00e9s un fitxer font d'eXeLearning v2. El contingut es mostrar\u00e0 en el frontend si hi ha HTML exportat disponible."
             ],
-            "Show Teacher Mode toggler": [
-                "Mostrar el commutador de Mode Professor"
+            "Show teacher layer selector": [
+                "Mostrar el selector de capa docent"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Si es desactiva, el selector de capa docent s'ocultar\u00e0 al contingut eXeLearning incrustat."
             ],
             "More download formats": [
                 "M\u00e9s formats de baixada"
diff --git a/languages/exelearning-ca_valencia.mo b/languages/exelearning-ca_valencia.mo
index 20ab3ec..1d89c86 100644
Binary files a/languages/exelearning-ca_valencia.mo and b/languages/exelearning-ca_valencia.mo differ
diff --git a/languages/exelearning-ca_valencia.po b/languages/exelearning-ca_valencia.po
index 249cd1d..deb0073 100644
--- a/languages/exelearning-ca_valencia.po
+++ b/languages/exelearning-ca_valencia.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "La còpia del fitxer pareix estar truncada."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Mostrar el commutador de Mode Professor"
+msgid "Show teacher layer selector"
+msgstr "Mostrar el selector de capa docent"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Alçada de la previsualització, en píxels."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Quan s'activa, el contingut es carrega amb el mode docent actiu."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Quan s'activa, s'ofereix el selector de capa docent perquè qui el veja puga mostrar el contingut docent."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Si es mostra el botó per commutar el mode docent."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Si es desactiva, el selector de capa docent s'ocultarà al contingut eXeLearning incrustat."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-de_DE-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-de_DE-4cf813b039eac98ce62f176afa8fc8fe.json
index b88c90c..38e1faa 100644
--- a/languages/exelearning-de_DE-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-de_DE-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Dies ist eine eXeLearning v2-Quelldatei. Der Inhalt wird im Frontend angezeigt, wenn exportiertes HTML verf\u00fcgbar ist."
             ],
-            "Show Teacher Mode toggler": [
-                "Umschalter f\u00fcr Lehrermodus anzeigen"
+            "Show teacher layer selector": [
+                "Lehrerebenen-Auswahl anzeigen"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Wenn deaktiviert, wird die Lehrerebenen-Auswahl im eingebetteten eXeLearning-Inhalt ausgeblendet."
             ],
             "More download formats": [
                 "Weitere Download-Formate"
diff --git a/languages/exelearning-de_DE.mo b/languages/exelearning-de_DE.mo
index 36913fe..fd16002 100644
Binary files a/languages/exelearning-de_DE.mo and b/languages/exelearning-de_DE.mo differ
diff --git a/languages/exelearning-de_DE.po b/languages/exelearning-de_DE.po
index e221a1b..9c9efe8 100644
--- a/languages/exelearning-de_DE.po
+++ b/languages/exelearning-de_DE.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "Die Dateikopie scheint abgeschnitten zu sein."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Umschalter für Lehrermodus anzeigen"
+msgid "Show teacher layer selector"
+msgstr "Lehrerebenen-Auswahl anzeigen"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Höhe der Vorschau in Pixeln."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Wenn aktiviert, wird der Inhalt mit aktivem Lehrermodus geladen."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Wenn aktiviert, wird die Lehrerebenen-Auswahl angeboten, damit Betrachter Lehrinhalte einblenden können."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Legt fest, ob die Umschaltfläche für den Lehrermodus angezeigt wird."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Wenn deaktiviert, wird die Lehrerebenen-Auswahl im eingebetteten eXeLearning-Inhalt ausgeblendet."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-eo-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-eo-4cf813b039eac98ce62f176afa8fc8fe.json
index d11377b..bfaaeba 100644
--- a/languages/exelearning-eo-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-eo-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "\u0108i tio estas eXeLearning v2 fontdosiero. La enhavo estos montrata en la fasado se eksportita HTML estas disponebla."
             ],
-            "Show Teacher Mode toggler": [
-                "Montri la \u015daltilon de Instruista Re\u011dimo"
+            "Show teacher layer selector": [
+                "Montri la elekton de instruista tavolo"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Se mal\u015daltita, la elekto de instruista tavolo estas ka\u015dita en la enkorpigita eXeLearning-enhavo."
             ],
             "More download formats": [
                 "Pliaj el\u015dutformatoj"
diff --git a/languages/exelearning-eo.mo b/languages/exelearning-eo.mo
index 2eb3203..c989fcd 100644
Binary files a/languages/exelearning-eo.mo and b/languages/exelearning-eo.mo differ
diff --git a/languages/exelearning-eo.po b/languages/exelearning-eo.po
index 82dbb9e..2eebdfe 100644
--- a/languages/exelearning-eo.po
+++ b/languages/exelearning-eo.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "La dosiera kopio ŝajnas esti trunkita."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Montri la ŝaltilon de Instruista Reĝimo"
+msgid "Show teacher layer selector"
+msgstr "Montri la elekton de instruista tavolo"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Alteco de la antaŭrigardo, en bilderoj."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Kiam ŝaltita, la enhavo ŝargiĝas kun la instruista reĝimo aktiva."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Kiam ŝaltita, la elekto de instruista tavolo estas proponata por ke spektantoj povu malkaŝi instruistan enhavon."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Ĉu la ŝaltbutono de la instruista reĝimo estas montrata."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Se malŝaltita, la elekto de instruista tavolo estas kaŝita en la enkorpigita eXeLearning-enhavo."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-es_ES-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-es_ES-4cf813b039eac98ce62f176afa8fc8fe.json
index cf446d4..e9cb5ea 100644
--- a/languages/exelearning-es_ES-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-es_ES-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -46,8 +46,8 @@
             "Height (px)": [
                 "Altura (px)"
             ],
-            "Show Teacher Mode toggler": [
-                "Mostrar el conmutador de Modo Docente"
+            "Show teacher layer selector": [
+                "Mostrar el selector de capa docente"
             ],
             "Download options": [
                 "Opciones de descarga"
@@ -67,6 +67,9 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Este es un archivo fuente de eXeLearning v2. El contenido se mostrar\u00e1 en el frontend si hay HTML exportado disponible."
             ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Si se desactiva, se ocultar\u00e1 el selector de capa docente en el contenido eXeLearning embebido."
+            ],
             "Web (_web.zip)": [
                 "Web (_web.zip)"
             ],
diff --git a/languages/exelearning-es_ES.mo b/languages/exelearning-es_ES.mo
index 3bab426..1b693e3 100644
Binary files a/languages/exelearning-es_ES.mo and b/languages/exelearning-es_ES.mo differ
diff --git a/languages/exelearning-es_ES.po b/languages/exelearning-es_ES.po
index a76667a..3650f9f 100644
--- a/languages/exelearning-es_ES.po
+++ b/languages/exelearning-es_ES.po
@@ -890,8 +890,8 @@ msgid "Height (px)"
 msgstr "Altura (px)"
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Mostrar el conmutador de Modo Docente"
+msgid "Show teacher layer selector"
+msgstr "Mostrar el selector de capa docente"
 
 #: assets/js/elp-upload.js:425
 msgid "Download options"
@@ -958,12 +958,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Altura de la previsualización, en píxeles."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Cuando se activa, el contenido se carga con el modo docente activo."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Cuando se activa, se ofrece el selector de capa docente para que quien lo vea pueda mostrar el contenido docente."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Si se muestra el botón para conmutar el modo docente."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Si se desactiva, se ocultará el selector de capa docente en el contenido eXeLearning embebido."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-eu-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-eu-4cf813b039eac98ce62f176afa8fc8fe.json
index 4a494e8..dc65694 100644
--- a/languages/exelearning-eu-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-eu-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Hau eXeLearning v2 iturburu fitxategia da. Edukia frontend-ean bistaratuko da esportatutako HTML eskuragarri badago."
             ],
-            "Show Teacher Mode toggler": [
-                "Erakutsi Irakasle Moduaren txandakatzailea"
+            "Show teacher layer selector": [
+                "Erakutsi irakasle-geruza hautatzailea"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Desaktibatuta badago, irakasle-geruza hautatzailea ezkutatuko da eXeLearning eduki txertatuan."
             ],
             "More download formats": [
                 "Deskarga-formatu gehiago"
diff --git a/languages/exelearning-eu.mo b/languages/exelearning-eu.mo
index fa088ac..16012f4 100644
Binary files a/languages/exelearning-eu.mo and b/languages/exelearning-eu.mo differ
diff --git a/languages/exelearning-eu.po b/languages/exelearning-eu.po
index 2279471..0221dad 100644
--- a/languages/exelearning-eu.po
+++ b/languages/exelearning-eu.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "Fitxategiaren kopia moztuta dagoela dirudi."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Erakutsi Irakasle Moduaren txandakatzailea"
+msgid "Show teacher layer selector"
+msgstr "Erakutsi irakasle-geruza hautatzailea"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Aurrebistaren altuera, pixeletan."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Gaituta dagoenean, edukia irakasle modua aktibatuta kargatzen da."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Aktibatzen denean, irakasle-geruza hautatzailea eskaintzen da ikusleek irakasle-edukia ager dezaten."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Irakasle moduaren txandakatze-botoia erakusten den ala ez."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Desaktibatuta badago, irakasle-geruza hautatzailea ezkutatuko da eXeLearning eduki txertatuan."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-gl_ES-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-gl_ES-4cf813b039eac98ce62f176afa8fc8fe.json
index bd8a632..c8765a2 100644
--- a/languages/exelearning-gl_ES-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-gl_ES-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Este \u00e9 un ficheiro fonte de eXeLearning v2. O contido mostrarase no frontend se hai HTML exportado dispo\u00f1ible."
             ],
-            "Show Teacher Mode toggler": [
-                "Mostrar o conmutador de Modo Profesor"
+            "Show teacher layer selector": [
+                "Amosar o selector de capa docente"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Se se desactiva, ocultarase o selector de capa docente no contido eXeLearning embebido."
             ],
             "More download formats": [
                 "M\u00e1is formatos de descarga"
diff --git a/languages/exelearning-gl_ES.mo b/languages/exelearning-gl_ES.mo
index b7178af..32f83e7 100644
Binary files a/languages/exelearning-gl_ES.mo and b/languages/exelearning-gl_ES.mo differ
diff --git a/languages/exelearning-gl_ES.po b/languages/exelearning-gl_ES.po
index 128776d..d998c55 100644
--- a/languages/exelearning-gl_ES.po
+++ b/languages/exelearning-gl_ES.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "A copia do ficheiro parece estar truncada."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Mostrar o conmutador de Modo Profesor"
+msgid "Show teacher layer selector"
+msgstr "Amosar o selector de capa docente"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Altura da vista previa, en píxeles."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Cando se activa, o contido cárgase co modo docente activo."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Cando se activa, ofrécese o selector de capa docente para que quen o vexa poida amosar o contido docente."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Se se amosa o botón para conmutar o modo docente."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Se se desactiva, ocultarase o selector de capa docente no contido eXeLearning embebido."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-it_IT-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-it_IT-4cf813b039eac98ce62f176afa8fc8fe.json
index 24c74bb..2c7cd85 100644
--- a/languages/exelearning-it_IT-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-it_IT-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Questo \u00e8 un file sorgente eXeLearning v2. Il contenuto sar\u00e0 visualizzato nel frontend se \u00e8 disponibile l'HTML esportato."
             ],
-            "Show Teacher Mode toggler": [
-                "Mostra il commutatore Modalit\u00e0 Docente"
+            "Show teacher layer selector": [
+                "Mostra il selettore del livello docente"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Se disattivato, il selettore del livello docente \u00e8 nascosto nel contenuto eXeLearning incorporato."
             ],
             "More download formats": [
                 "Altri formati di download"
diff --git a/languages/exelearning-it_IT.mo b/languages/exelearning-it_IT.mo
index fdd7d1c..16f0af3 100644
Binary files a/languages/exelearning-it_IT.mo and b/languages/exelearning-it_IT.mo differ
diff --git a/languages/exelearning-it_IT.po b/languages/exelearning-it_IT.po
index 6626e91..9b9092b 100644
--- a/languages/exelearning-it_IT.po
+++ b/languages/exelearning-it_IT.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "La copia del file sembra essere troncata."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Mostra il commutatore Modalità Docente"
+msgid "Show teacher layer selector"
+msgstr "Mostra il selettore del livello docente"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Altezza dell'anteprima, in pixel."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Se attivato, il contenuto viene caricato con la modalità docente attiva."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Se attivato, viene offerto il selettore del livello docente così gli spettatori possono mostrare i contenuti per docenti."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Indica se viene mostrato il pulsante di attivazione della modalità docente."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Se disattivato, il selettore del livello docente è nascosto nel contenuto eXeLearning incorporato."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-pt_PT-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-pt_PT-4cf813b039eac98ce62f176afa8fc8fe.json
index b6965fd..74e7886 100644
--- a/languages/exelearning-pt_PT-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-pt_PT-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Este \u00e9 um ficheiro fonte eXeLearning v2. O conte\u00fado ser\u00e1 apresentado no frontend se houver HTML exportado dispon\u00edvel."
             ],
-            "Show Teacher Mode toggler": [
-                "Mostrar o comutador do Modo Professor"
+            "Show teacher layer selector": [
+                "Mostrar o seletor de camada docente"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Se desativado, o seletor de camada docente fica oculto no conte\u00fado eXeLearning incorporado."
             ],
             "More download formats": [
                 "Mais formatos de transfer\u00eancia"
diff --git a/languages/exelearning-pt_PT.mo b/languages/exelearning-pt_PT.mo
index 176e497..e9a1810 100644
Binary files a/languages/exelearning-pt_PT.mo and b/languages/exelearning-pt_PT.mo differ
diff --git a/languages/exelearning-pt_PT.po b/languages/exelearning-pt_PT.po
index 1b9d8be..4fd2ace 100644
--- a/languages/exelearning-pt_PT.po
+++ b/languages/exelearning-pt_PT.po
@@ -393,8 +393,8 @@ msgid "File copy appears truncated."
 msgstr "A cópia do ficheiro parece estar truncada."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Mostrar o comutador do Modo Professor"
+msgid "Show teacher layer selector"
+msgstr "Mostrar o seletor de camada docente"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -652,12 +652,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Altura da pré-visualização, em pixels."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Quando ativado, o conteúdo carrega com o modo professor ativo."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Quando ativado, o seletor de camada docente é disponibilizado para que os visitantes possam revelar o conteúdo para docentes."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Define se o botão de alternância do modo professor é mostrado."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Se desativado, o seletor de camada docente fica oculto no conteúdo eXeLearning incorporado."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning-ro_RO-4cf813b039eac98ce62f176afa8fc8fe.json b/languages/exelearning-ro_RO-4cf813b039eac98ce62f176afa8fc8fe.json
index 7665876..7144eb7 100644
--- a/languages/exelearning-ro_RO-4cf813b039eac98ce62f176afa8fc8fe.json
+++ b/languages/exelearning-ro_RO-4cf813b039eac98ce62f176afa8fc8fe.json
@@ -43,8 +43,11 @@
             "This is an eXeLearning v2 source file. The content will be displayed on the frontend if exported HTML is available.": [
                 "Acesta este un fi\u0219ier surs\u0103 eXeLearning v2. Con\u021binutul va fi afi\u0219at \u00een frontend dac\u0103 HTML-ul exportat este disponibil."
             ],
-            "Show Teacher Mode toggler": [
-                "Afi\u0219eaz\u0103 comutatorul Mod Profesor"
+            "Show teacher layer selector": [
+                "Afi\u0219eaz\u0103 selectorul stratului pentru profesori"
+            ],
+            "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content.": [
+                "Dac\u0103 este dezactivat, selectorul stratului pentru profesori este ascuns \u00een con\u021binutul eXeLearning \u00eencorporat."
             ],
             "More download formats": [
                 "Mai multe formate de desc\u0103rcare"
diff --git a/languages/exelearning-ro_RO.mo b/languages/exelearning-ro_RO.mo
index bb01541..99776f9 100644
Binary files a/languages/exelearning-ro_RO.mo and b/languages/exelearning-ro_RO.mo differ
diff --git a/languages/exelearning-ro_RO.po b/languages/exelearning-ro_RO.po
index e5bfbe8..a0b33da 100644
--- a/languages/exelearning-ro_RO.po
+++ b/languages/exelearning-ro_RO.po
@@ -394,8 +394,8 @@ msgid "File copy appears truncated."
 msgstr "Copia fișierului pare a fi trunchiată."
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
-msgstr "Afișează comutatorul Mod Profesor"
+msgid "Show teacher layer selector"
+msgstr "Afișează selectorul stratului pentru profesori"
 
 #: includes/class-exelearning-editor.php:179
 #: includes/class-exelearning-editor.php:212
@@ -656,12 +656,13 @@ msgid "Height of the preview, in pixels."
 msgstr "Înălțimea previzualizării, în pixeli."
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
-msgstr "Când este activat, conținutul se încarcă cu modul profesor activ."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
+msgstr "Când este activat, selectorul stratului pentru profesori este oferit pentru ca vizitatorii să poată afișa conținutul pentru profesori."
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
-msgstr "Dacă este afișat butonul de comutare a modului profesor."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
+msgstr "Dacă este dezactivat, selectorul stratului pentru profesori este ascuns în conținutul eXeLearning încorporat."
 
 #: admin/class-admin-settings.php:135
 msgid "When enabled, shows a multi-format download button."
diff --git a/languages/exelearning.pot b/languages/exelearning.pot
index 929c2e6..7381a5a 100644
--- a/languages/exelearning.pot
+++ b/languages/exelearning.pot
@@ -89,11 +89,12 @@ msgid "Height of the preview, in pixels."
 msgstr ""
 
 #: admin/class-admin-settings.php:125
-msgid "When enabled, the content loads with teacher mode active."
+msgid "When enabled, the teacher layer selector is offered so viewers can reveal teacher content."
 msgstr ""
 
 #: admin/class-admin-settings.php:130
-msgid "Whether the teacher-mode toggle button is shown."
+#: assets/js/elp-upload.js:414
+msgid "If disabled, the teacher layer selector is hidden in the embedded eXeLearning content."
 msgstr ""
 
 #: admin/class-admin-settings.php:135
@@ -997,7 +998,7 @@ msgid "Height (px)"
 msgstr ""
 
 #: assets/js/elp-upload.js:413
-msgid "Show Teacher Mode toggler"
+msgid "Show teacher layer selector"
 msgstr ""
 
 #: assets/js/elp-upload.js:425
diff --git a/public/class-shortcodes.php b/public/class-shortcodes.php
index e58d1f6..ddba178 100644
--- a/public/class-shortcodes.php
+++ b/public/class-shortcodes.php
@@ -43,7 +43,7 @@ public function display_exelearning( $atts, $content = null ) { // phpcs:ignore
 				'id'                   => 0,
 				'height'               => 600,
 				'teacher_mode'         => '0',
-				'teacher_mode_visible' => '1',
+				'teacher_mode_visible' => '0',
 				'show_download'        => '0',
 				'download_formats'     => '',
 				'screenshot'           => 'no',
@@ -313,6 +313,17 @@ private function render_preview( $title, $preview_url, $height, $file_url, $teac
 		$unique_id = 'exelearning-' . wp_unique_id();
 		$is_poster = '' !== $poster_url;
 
+		// Teacher-mode visibility is owned by eXeLearning core: exported packages hide
+		// teacher-only content by default and expose an in-page "teacher layer" selector
+		// through ?exe-teacher=1 (the selector appears but stays off until the viewer
+		// turns it on). No host-side CSS/JS injection is needed — we carry the request on
+		// the iframe src whenever this embed should offer the selector. The legacy
+		// teacher_mode attribute (activate-on-load) folds into the same opt-in, since
+		// core deliberately no longer auto-reveals from the URL.
+		if ( $teacher_mode_visible || $teacher_mode ) {
+			$preview_url .= ( false === strpos( $preview_url, '?' ) ? '?' : '&' ) . 'exe-teacher=1';
+		}
+
 		$fallback_download = sprintf(
 			'<a href="%s" class="exelearning-toolbar-btn" download title="%s">
                 <span class="dashicons dashicons-download"></span>
@@ -379,24 +390,23 @@ class="exelearning-iframe"
 			esc_attr__( 'View fullscreen', 'exelearning' ),
 			$poster_html,
 			$iframe_html,
-			$this->render_preview_script( $unique_id, $teacher_mode_visible, $teacher_mode, $is_poster )
+			$this->render_preview_script( $unique_id, $is_poster )
 		);
 	}
 
 	/**
 	 * Build the inline behavior script for a preview iframe.
 	 *
-	 * Optional behaviors (poster click-to-load, hiding the teacher-mode toggler,
-	 * activating teacher mode) are only emitted when requested, so the rendered
-	 * markup stays minimal when they are not in use.
+	 * Teacher-mode visibility is handled by eXeLearning core through the
+	 * ?exe-teacher=1 query parameter on the iframe src, so no host-side CSS/JS
+	 * injection is emitted here. The script only wires the optional poster
+	 * click-to-load behavior.
 	 *
-	 * @param string $unique_id            Container element ID.
-	 * @param bool   $teacher_mode_visible Whether the teacher-mode toggler stays visible.
-	 * @param bool   $teacher_mode         Whether teacher mode should be activated on load.
-	 * @param bool   $is_poster            Whether the iframe loads lazily from a poster.
+	 * @param string $unique_id Container element ID.
+	 * @param bool   $is_poster Whether the iframe loads lazily from a poster.
 	 * @return string Inline <script> markup.
 	 */
-	private function render_preview_script( $unique_id, $teacher_mode_visible, $teacher_mode, $is_poster ) {
+	private function render_preview_script( $unique_id, $is_poster ) {
 		$body = '';
 
 		if ( $is_poster ) {
@@ -414,45 +424,6 @@ private function render_preview_script( $unique_id, $teacher_mode_visible, $teac
                     }';
 		}
 
-		if ( ! $teacher_mode_visible ) {
-			$body .= '
-                    if (iframe) {
-                        var hideCss = "#teacher-mode-toggler-wrapper { visibility: hidden !important; }";
-                        var injectHide = function() {
-                            try {
-                                if (!iframe.contentDocument) return;
-                                var d = iframe.contentDocument;
-                                if (d.getElementById("exelearning-teacher-mode-style")) return;
-                                var st = d.createElement("style");
-                                st.id = "exelearning-teacher-mode-style";
-                                st.textContent = hideCss;
-                                (d.head || d.documentElement).appendChild(st);
-                            } catch (e) {}
-                        };
-                        iframe.addEventListener("load", injectHide);
-                        injectHide();
-                    }';
-		}
-
-		if ( $teacher_mode ) {
-			$body .= '
-                    if (iframe) {
-                        var activate = function() {
-                            try {
-                                if (!iframe.contentDocument) return;
-                                var root = iframe.contentDocument.documentElement;
-                                if (!root) return;
-                                root.classList.add("mode-teacher");
-                                var toggler = iframe.contentDocument.getElementById("teacher-mode-toggler");
-                                if (toggler) toggler.checked = true;
-                                try { iframe.contentWindow.localStorage.setItem("exeTeacherMode", "1"); } catch (e) {}
-                            } catch (e) {}
-                        };
-                        iframe.addEventListener("load", activate);
-                        activate();
-                    }';
-		}
-
 		return sprintf(
 			'<script>
                 (function() {
diff --git a/readme.txt b/readme.txt
index 8487b96..eba99e5 100644
--- a/readme.txt
+++ b/readme.txt
@@ -31,9 +31,9 @@ Upload your `.elpx` file to the Media Library, then embed it either with the eXe
 
 `id` (required), `height`, `teacher_mode`, `teacher_mode_visible`, `show_download`, `download_formats` and `screenshot`. See the full shortcode reference at https://github.com/exelearning/wp-exelearning/blob/main/docs/SHORTCODES.md.
 
-= How do I start content in teacher mode? =
+= How do I reveal teacher-only content? =
 
-Add `teacher_mode="1"` to the shortcode, for example `[exelearning id="123" teacher_mode="1"]`. Use `teacher_mode_visible="0"` to also hide the teacher-mode toggle.
+eXeLearning packages hide teacher-only content by default, and the teacher layer selector is also hidden unless you enable it. Add `teacher_mode_visible="1"` to the shortcode, for example `[exelearning id="123" teacher_mode_visible="1"]`, to make that selector available; the viewer then turns it on. A bare embed keeps the selector hidden.
 
 = How do I show the package screenshot? =
 
diff --git a/tests/unit/ElpUploadBlockTest.php b/tests/unit/ElpUploadBlockTest.php
index 9368017..10b73cf 100644
--- a/tests/unit/ElpUploadBlockTest.php
+++ b/tests/unit/ElpUploadBlockTest.php
@@ -87,6 +87,67 @@ public function test_render_block_with_preview() {
 		$this->assertStringContainsString( $hash, $result );
 	}
 
+	/**
+	 * By default the block does NOT offer the teacher layer selector: the
+	 * package keeps teacher-only content hidden and no ?exe-teacher parameter is
+	 * appended to the iframe src until the author enables the control.
+	 */
+	public function test_block_hides_teacher_selector_by_default() {
+		$attachment_id = $this->factory->attachment->create();
+		$hash          = str_repeat( 'd', 40 );
+		update_post_meta( $attachment_id, '_exelearning_extracted', $hash );
+		update_post_meta( $attachment_id, '_exelearning_has_preview', '1' );
+
+		$result = $this->block->render_block( array( 'attachmentId' => $attachment_id ) );
+
+		$this->assertStringContainsString( '<iframe', $result );
+		$this->assertStringNotContainsString( 'exe-teacher', $result );
+		$this->assertStringNotContainsString( 'teacher-mode-toggler-wrapper', $result );
+	}
+
+	/**
+	 * teacherModeVisible=true offers the selector through the package's
+	 * ?exe-teacher=1 URL parameter, without injecting any CSS/JS.
+	 */
+	public function test_block_offers_teacher_selector_when_enabled() {
+		$attachment_id = $this->factory->attachment->create();
+		$hash          = str_repeat( 'd', 40 );
+		update_post_meta( $attachment_id, '_exelearning_extracted', $hash );
+		update_post_meta( $attachment_id, '_exelearning_has_preview', '1' );
+
+		$result = $this->block->render_block(
+			array(
+				'attachmentId'       => $attachment_id,
+				'teacherModeVisible' => true,
+			)
+		);
+
+		$this->assertStringContainsString( '<iframe', $result );
+		$this->assertStringContainsString( 'exe-teacher=1', $result );
+		$this->assertStringNotContainsString( 'teacher-mode-toggler-wrapper', $result );
+	}
+
+	/**
+	 * teacherModeVisible=false hides the selector: no ?exe-teacher parameter is
+	 * appended to the iframe src.
+	 */
+	public function test_block_hides_teacher_selector_when_disabled() {
+		$attachment_id = $this->factory->attachment->create();
+		$hash          = str_repeat( 'e', 40 );
+		update_post_meta( $attachment_id, '_exelearning_extracted', $hash );
+		update_post_meta( $attachment_id, '_exelearning_has_preview', '1' );
+
+		$result = $this->block->render_block(
+			array(
+				'attachmentId'       => $attachment_id,
+				'teacherModeVisible' => false,
+			)
+		);
+
+		$this->assertStringContainsString( '<iframe', $result );
+		$this->assertStringNotContainsString( 'exe-teacher', $result );
+	}
+
 	/**
 	 * Test block uses proxy URL instead of direct URL.
 	 */
diff --git a/tests/unit/ShortcodesTest.php b/tests/unit/ShortcodesTest.php
index aae0647..4f1db95 100644
--- a/tests/unit/ShortcodesTest.php
+++ b/tests/unit/ShortcodesTest.php
@@ -323,34 +323,80 @@ private function create_previewable_attachment( $hash, $with_screenshot = false
 	}
 
 	/**
-	 * Test teacher_mode is off by default (no activation script injected).
+	 * By default the teacher layer selector is NOT available: the package keeps
+	 * teacher-only content hidden and no ?exe-teacher parameter is appended.
 	 */
-	public function test_teacher_mode_off_by_default() {
+	public function test_teacher_selector_hidden_by_default() {
 		$attachment_id = $this->create_previewable_attachment( str_repeat( '1', 40 ) );
 
 		$result = $this->shortcodes->display_exelearning( array( 'id' => $attachment_id ) );
 
 		$this->assertStringContainsString( '<iframe', $result );
+		$this->assertStringNotContainsString( 'exe-teacher', $result );
 		$this->assertStringNotContainsString( 'mode-teacher', $result );
 		$this->assertStringNotContainsString( 'exeTeacherMode', $result );
+		$this->assertStringNotContainsString( 'teacher-mode-toggler-wrapper', $result );
 	}
 
 	/**
-	 * Test teacher_mode="1" injects the teacher-mode activation script.
+	 * teacher_mode_visible="1" makes the selector available, carried on the
+	 * iframe src via ?exe-teacher=1, and no CSS/JS is injected into the package.
 	 */
-	public function test_teacher_mode_activation() {
+	public function test_teacher_selector_available_when_visibility_on() {
+		$attachment_id = $this->create_previewable_attachment( str_repeat( '1', 40 ) );
+
+		$result = $this->shortcodes->display_exelearning(
+			array(
+				'id'                   => $attachment_id,
+				'teacher_mode_visible' => '1',
+			)
+		);
+
+		$this->assertStringContainsString( '<iframe', $result );
+		$this->assertStringContainsString( 'exe-teacher=1', $result );
+		$this->assertStringNotContainsString( 'mode-teacher', $result );
+		$this->assertStringNotContainsString( 'exeTeacherMode', $result );
+		$this->assertStringNotContainsString( 'teacher-mode-toggler-wrapper', $result );
+	}
+
+	/**
+	 * teacher_mode_visible="0" hides the selector: no ?exe-teacher parameter is
+	 * appended and nothing is injected into the package.
+	 */
+	public function test_teacher_selector_hidden_when_visibility_off() {
 		$attachment_id = $this->create_previewable_attachment( str_repeat( '2', 40 ) );
 
 		$result = $this->shortcodes->display_exelearning(
 			array(
-				'id'           => $attachment_id,
-				'teacher_mode' => '1',
+				'id'                   => $attachment_id,
+				'teacher_mode_visible' => '0',
 			)
 		);
 
 		$this->assertStringContainsString( '<iframe', $result );
-		$this->assertStringContainsString( 'mode-teacher', $result );
-		$this->assertStringContainsString( 'exeTeacherMode', $result );
+		$this->assertStringNotContainsString( 'exe-teacher', $result );
+		$this->assertStringNotContainsString( 'teacher-mode-toggler-wrapper', $result );
+	}
+
+	/**
+	 * teacher_mode="1" offers the selector through ?exe-teacher=1 even when
+	 * teacher_mode_visible is off (it no longer auto-reveals via injected JS).
+	 */
+	public function test_teacher_mode_attr_offers_selector() {
+		$attachment_id = $this->create_previewable_attachment( str_repeat( '3', 40 ) );
+
+		$result = $this->shortcodes->display_exelearning(
+			array(
+				'id'                   => $attachment_id,
+				'teacher_mode'         => '1',
+				'teacher_mode_visible' => '0',
+			)
+		);
+
+		$this->assertStringContainsString( '<iframe', $result );
+		$this->assertStringContainsString( 'exe-teacher=1', $result );
+		$this->assertStringNotContainsString( 'mode-teacher', $result );
+		$this->assertStringNotContainsString( 'exeTeacherMode', $result );
 	}
 
 	/**