Grab is a utility that is already on your Mac! It allows students to capture their work and save it as a picture. Students can then insert the picture in a Word document and write about it.
How many different triangles can you create that has an area of 1 squared unit? Describe the triangles you created.
Here are some instructions I found on an Apple support website. The language is fairly friendly so you can actually give students a copy.
Grab is also great for you! Think of all the images you can save and use to make up worksheets, posters etc.