PHeT is a collection of interactive HTML based simulations mostly for K-12 covering all aspects of science and math.
You do have to register for the site, but it is free.
After you register, sign-in and you can access all of these simulation tools. Most of them can be downloaded to your desktop.
I’ve used a few of these in my physics classes. The visual quality it mixed, but some are very good.
The best one for showing simple electrical circuits is the circuit construction kit virtual lab.
It’s easy to build a simple circuit by selecting circuit elements, placing them on a page and connecting them with wires. Then you can simulate the transient voltage response using a switch or reseting the charge on a capacitor or current through an inductor.
This is not a substitute for a real SPICE simulator, but is a simple start to show the electron flow and the impact of changing a battery voltage, or resistance value of even the transient response of an RL, RC or RLC circuit.
In addition to the display of current flow, you can add voltmeters, ammeters and a scope. Here is an example of the scope output:
Definitely worth checking out.
