Could my characters solve a Rubik's Cube?

Impulse-era Bart would never manage to stick it out long enough to learn the patterns, but later Bart definitely would be able to if he had a reason

Sleeper probably could, but would rather try to get someone else to an take all the credit or something equally amusing.

Claudia? She's the person who very carefully rearranged the stickers on one corner of the cube to render it unsolvable just to see how long it took folks to figure that out.