And it holds... maybe you'll need to upgrade to 2 sets of magnets once you have a few files in your folder.

I think there's a strong possibility here to look at ways we assign students jobs, how students queue up for conferencing or correction of their work, how teachers recognize student of the week etc. (And instantly I think of a particular student, who'd I reverse the magnets and then show him "See, I can't make you student of the week, it just can't happen." Only joking.

Round Magnets, 3D nets, patterns, shapes and symmetry

Tricks with the round ones

And this is exactly what the flat ones do.

These things are strong! A point that can be made no better than by watching this video (they use much bigger magnets):

Does Free Energy Exist?

Or does this look more like it? Everything is home made.

Actually, it could be a fun class project

This looks like fun, the type of magnets for sale here too! Get an old CD with some sticky tape (or super glue), and you can do the same...

This one adds the power of gravity... and it looks fun to replicate...

I like this one - it starts out simple, sets up a realistic challenge, and then goes all crazy into conspiracy theories.

I like how they all use materials that could be found in a school or at home anyway

I like the explanations in this one. It sounds like a reasonable explanation by a student, and a challenge that would certainly get students motivated.

And the ultimate physics class challenge

And if magnets are not your thing, have a look at the SpaceRail devices available to purchase.