Very clever! Joining the ranks of snap circuits [1] and others. I like the magnet trick [2]. The challenge I've found with them though is that some inexpensive test equipment to explore would be helpful too. I keep hoping something like the 'nanoscope' or some other inexpensive oscilloscope product can be 'built in' to one of these things so that students and see what is going on with their eyes.

[1] http://www.elenco.com/product/productlist/snap_circuits

[2] I wonder if Apple will sue them if they do that for a power connector? (not snark, seriously, Apple is all about keeping MagSafe for themselves ...)