Recently, the Maketronix Alarm kit was fully-funded on IndieGoGo. It is an add-on board and sensor for the Raspberry Pi that allows you to put together your own movement-activated alarm system. It comes with educational material that can be used in the classroom.
Finding that the material doesn’t use the (much easier) GPIO Zero, Richard Hayler set about writing his own GPIO Zero version of the software. Take a look at Richard’s post here and his code on GitHub here.