The ones I'm making need the use of a laser cutter or other CNC equipment, but towards the end (step 4), I'll explain a couple of ways to do this by hand too.
access to CAD software
access to a laser cutter
3mm thick acrylic
On the last page of this instructable, there are some curriculum links - I've done this with my students, maybe you'll find somewhere to include it in a project with yours too.
Step 1: Design your buttons
Simple tends to work best!
So that the laser cutter can "read" the pictures, I've changed the colour of my cutting lines to red, and the engraving lines to black.