What my professor did for my aircraft rec class was show us 3 or 4 different pictures of the same aircraft and point out the unique parts of it that make it recognizable (landing gear, windows, exit doors, etc) and then on the tests he’d give us a completely different picture (not one that was originally shown) so we really had to know what to look for instead of just memorizing a picture. It was really effective. I’d recommend trying to do something similar to study.