step-by-step button cap

One of the schools I work with makes heavy use of these step-by-step jelly bean buttons. They run into a fairly consistent problem though of the button being accidentally pressed when it's in a bag or when a remote switch is being used, so I came up with these magnetic caps. You'll need 3 5mm disc magnets if you want the cap to hold itself on, but it should friction fit pretty well without them.