A sentence like: "Prompt them by asking what happens when they touch both leads to the positive terminal." I am going with a period, but maybe that should have a question mark? I could, of course, solve the problem by adding quotes (ie "Prompt them by asking, "What happens when they touch both leads to the positive terminal?" but I don't want to.) Here is the real issue: the full paragraph will be as follows: Prompt them by asking what happens when they touch both leads to the positive terminal. To the negative terminal? Positive to negative; negative to positive? Positive to positive; negative to negative? That is the way I have it right now, but I find it a little strange that my intuition is not consistent, as my first sentence uses a period, but all of the fragments use question marks. Does this bug anyone, or does this work?
"Prompt them by asking what happens when they touch both leads to the positive terminal." This is fine. The speaker isn't asking a question, so no question mark needed.
I like items that are different aspects of the same scenario in list form. This allows me to see similarities and differences more easily, as it takes on illustrative form vs purely literary form. ie paints a literal picture. Prompt them by asking, what happens when they touch both leads: to the positive terminal? to the negative terminal? positive to negative; negative to positive? positive to positive; negative to negative?
Otherwise, I'd compress it but keep the format: Prompt them by asking: what happens when they touch both leads to the positive terminal? To the negative terminal? Positive to negative; negative to positive? Positive to positive; negative to negative? I have no idea how many grammatical rules this violates, or how many puppies die each time it is read. Sorry.