if quantum mechanics has to popularise

 for Topology cheap elastic rubber bands are the easiest choice.

but for Particle stuff, the only way to show is using High Energy, which has issues (CERN has a mobile dialer do you care to know!) here is the toy I find best to teach very young how to conceptualize. It is expensive as hell, I am yet to pick one up, takes a lot to muster, but this is spot on, and with Chromodynamics getting mainstream viability this is surely the shortest way to better the value of a smartphone or TV screen 

Toysmith Eulers Disk Create A Hypnotic Display Of Light And Sound | Desertcart INDIA