> ## Documentation Index
> Fetch the complete documentation index at: https://docs.goguardian.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Commands Overview
> Reference guide to all GoGuardian Teacher commands for managing student devices during an active class session.
Teacher commands let you interact with student devices during an active class session. Most commands can be applied to a single student or multiple students at once.
## Available Commands
| Command | What It Does |
| ----------------------------- | ----------------------------------------------------------------------------------------------------------- |
| **Lock / Unlock Screen** | Mutes and disables all browser windows on student devices. Unlocks automatically when the session ends. |
| **Open Tab** | Opens a specified URL in a new tab on selected students' browsers. |
| **Close Tab** | Closes an active or background tab on a student's browser. |
| **Screenshot** | Captures a screenshot of a student's current screen. Saved to the Screenshots tab. |
| **Exclude / Include Student** | Temporarily hides an absent student from Screens and Timeline views without removing them from the roster. |
| **Annotate** | Places a colored circle on a student's screen to highlight a section. Visible for approximately 10 seconds. |
| **Close App** | Closes any application running on a student's Windows device. Windows standalone only. |
| **Teacher Chat** | Sends a text message to an individual student or broadcasts an announcement to the whole class. |
## Lock / Unlock Screen
The Lock Screen command mutes and disables all browser windows on a student's device. The lock clears automatically at the end of the session in which the student was locked.
If a locked student joins another teacher's session before the first session ends, the lock carries over. Any teacher with an active session can unlock the student. A locked student's tile always shows "You have locked this student's screen" regardless of which teacher issued the lock.
**Lock one student:** Click the 3-dot menu on their tile and select **Lock student's device**.
**Lock multiple students:**
1. Select students using the checkboxes next to their names.
2. Click **Lock / Unlock device**.
3. Optionally enter a custom message for the locked screen.
4. Click **Lock devices** to confirm.
**Unlock students:**
1. Select the locked students.
2. Click **Lock / Unlock device**.
3. Click **Unlock**, then confirm by clicking **Unlock devices**.
If the device does not unlock after 30 seconds, restart the student's device, wait for them to reconnect to the session, then issue the unlock command again.
Lock Screen only disables browser windows. Applications running outside of the browser are not affected by this command.
## Open Tab
The Open Tab command opens a specified URL in a new tab on selected students' devices.
**Open a tab for multiple students:**
1. Click **Open Tab**.
2. Select **All** or choose specific students, then click **Next**.
3. Enter a URL and click **Open Tab**.
**Open a tab for one student:**
1. Click the 3-dot menu on a student's tile.
2. Select **Open Tab**.
3. Enter a URL and click **Open Tab**.
The Open Tab command requires students to have a Chrome window open. If a student shows "no active tab," ask them to open Chrome first, then issue the command.
## Close Tab
1. Click the student's tile to open their screen view.
2. Find the tab you want to close.
3. Click **Close** to the right of the URL.
Depending on network speed, it can take up to 10 seconds for a closed tab to disappear from the Teacher dashboard.
## Screenshot
1. Click a student's tile to open their screen view.
2. Click the camera icon in the bottom-right corner.
Screenshots are saved in the **Screenshots** tab. See [Take a Screenshot](/products/teacher/take-a-screenshot) for how to access and download saved screenshots.
## Exclude / Include Student
Excluding a student hides them from Screens and Timeline views. It does not remove them from the roster.
**Exclude one student:** Click the 3-dot menu on their tile and select **Exclude student**.
**Exclude multiple students:**
1. Click **Exclude from session**.
2. Select **All** or specific students.
3. Click **Exclude students** to confirm.
**Re-include a student:** Find the excluded student's tile and click **Re-include Student**.
## Annotate
The Annotate command places a colored circle on a student's screen. The circle is visible to the student for approximately 10 seconds, then disappears automatically. You can change the circle's color and size using the **Pointer Color** and **Pointer Size** options.
Annotate requires GoGuardian App 26.2.0 or later on the student's device, or the GoGuardian browser extension. Annotate is not supported on iPadOS. GoGuardian extensions support annotations only within the student's browser.
The Annotate option is available in the bottom-right area of a student's screen view.
## Close App (Windows Standalone Only)
The Close App command closes any application running on a Windows student device. This command is available only when the GoGuardian for Windows standalone software is installed on the student's device.
## Issue Commands to One Student From Their Tile
From the 3-dot menu in the top-right corner of any student's tile, you can issue these commands directly to that student:
* Lock / Unlock Screen
* Open Tab
* Exclude Student
* Start a Chat (when Chat is enabled for the session)
## Resources
Detailed steps and troubleshooting for the Lock Screen command.
Capture and access screenshots of student screens.
Review the full Screens view layout and controls.
Send messages to individual students or broadcast to the class.