I am writing a book with Kim Mattina on Google Jamboard. She has a tip to add a giant textbox over the frame to prevent students from accidentally moving objects on the frame. I thought, you can lock backgrounds on a Jam why would you do this? She pointed to this sample Jam by Bridgid Duncan with a graphic organizer that has Sticky Notes as part of the graphic organizer. There is a giant textbox on the top layer to prevent the moving of the elements in the graphic organizer.
Create a Textbox
On a frame in the Jam, click on the Text Box option.
Use the resizing handle in the bottom left corner to expand the size of the textbox so that it covers the entire frame. Anything below the textbox will be inaccessible since the textbox is in the way.
Transparent Rectangle or Giant Textbox
A textbox does the trick. It’s quick and easy since the Text Box tool is right there in the Jam. However, I think it is a little awkward to get the textbox big enough to cover the whole frame. I would recommend trying a transparent rectangle.
In the Jam click on the “Add Image” icon in the side toolbar.
Add the transparent rectangle to the Jam by uploading the image file. Resize the transparent rectangle to cover the entire frame.
How I made the transparent rectangle is I created a new Google Drawing.
By default a Google Drawing canvas has a transparent background. Name the Drawing and do literally NOTHING to the drawing.
Download the PNG File
It is really important that you download your Google Drawing as a PNG file. PNG supports transparency. JPEG does not.
Use the File menu in the Google Drawing to choose “PNG image.” This downloads the transparent rectangle to your computer. Upload this to your Jam!