When creating or editing a lesson in Lesson Builder, only the teacher cards are displayed by default. 

Teacher Cards

To add a new teacher card, click on an existing teacher card or a section and select the cog icon. Select Add Card.
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Alternatively, click the Add New Card icon at the bottom of the page, and select Add Card
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Student Cards

To add a student card, you first need to display the student card track. Click the Teacher/Student icon at the bottom of the page. 
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Teacher cards and placeholders for student cards will be displayed side by side. 
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Create a new student card by clicking on the placeholder next to the relevant teacher card. By default, when you present your lesson, student cards are automatically sent to students when you select or navigate to the corresponding teacher card. If you prefer to decide when to send the student card (for example, after discussing the content on the teacher card), click the cog icon on the student card and untick Auto-Send Card
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Sometimes you may choose to duplicate the teacher card and send that to your students for a closer look on their personal devices. To copy the contents of the teacher card to a student card, simply click on the relevant teacher card, click the cog icon and select Duplicate to Student Card.
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