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Here is a guide on how to add a text header as a module item?
You can add text to your module when you add a new item.
Open Modules
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In Course Navigation, click the Modules link.
Add Content
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Click the Add Item button.
Select Item Type
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In the drop-down menu, select the Text Header option.
Add Text
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Type the text you wish to add in the header field [1]. Open the Indentation drop-down menu and select the level of indentation for the text header [2].
Add Item
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Click the Add Item button.
View Module
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View the new text header in your module.