Circuitous (Beta - Looking For Feedback)

Good start, but needs some expansion. More (and harder) levels would be a good way to go. For example, a level that requires multiple circuits with different amps to win and you have to properly match up 4 or more batteries, light bulbs, and resistors. Nice learning tool as is, but has the makings of also being a fun puzzle game.

Would be a good learning tool with a sandbox mode and adjustable values for the components.

Good graphics, good performance. A bit too easy in my opinion, but that's expected for educational games. Needs more levels. Also, the last level shouldn't just show a "next level" button that does nothing. Also, it would be nice to have a way to create wire crossing.

Why do I get scroll bars inside the game window, as if it doesn't fit the alloted space?

It seems to be fine with parallel light bulbs and resistors, however it seems to go a little odd when you put batteries in parallel.
On further investigation that isn't the case if the wires are of equal length along both branches (do the wires have hidden resistance values? that would explain it) and there are no dead end branches/'loose wires' (for some reason this causes a current drop on one battery without effecting anything else) or if you give the batteries non-zero resistance values.