Helpful info but.. bak to the circuit... I guess the physics teacher is confused because, when I showed him your circuit, and asked how to place the transistors, he looked at it and said he thought that eletrons would flow from the negative of the solar panel, and so he didn't know why it would go to the negative of the batteries but... In my hardware engineeriing class, another guy told me that the physics teacher is thinking about it opposite to how it really is (he said that the way you'd get taught in physics is exact opposite of what you would do in applications like this... I don't understand that but I went with it because When we tested it out, it lit up the LED's... )
Anyways, the way I'm seeing the altered schematic with the transistor on it is this: instead of a positive going aross the top from the solar panel, across all the LEDs, the positive would go striaght across the LED's and not connect to them, but onnect to the battery (which trminal on the battery? the positive or negative?) And out of that connection, the transistor would exist that would switch the flow from Solar Panel To battries to Batteries to LED (with the negative sides of the LED's all connected like in the diagram you sent, still)
Does that work?