Ugh. All growing up I struggled with this. On all standardized tests I hit it out of the park and tested far beyond my current level. But on tests that required route memorization and a lot of concentration, I had a hell of a time. Especially homework every night. If you look at a list of ADHD symptoms, I have basically every one of them in spades, though when I was a kid this was not diagnosed much if ever.

Even the fixation on useless points of theory over the practical tested materials I identify with. My brain just naturally wants to think about what interests it, and if there is not some sort of honest connection to a real curiosity I have on the subject, I'm kind of screwed. Luckily I'm a curious person as a matter of principle, but again, it made studying difficult.

Maybe meds would have helped, but the bottom line is that I just had to brute force it. When I wanted to succeed I did fine by brute forcing it. When I was younger and there wasn't yet a tangible connection between my performance and things like getting into the college of my choice, my grades suffered as I didn't have the extra discipline that was required.

For the subject requiring route memorization, what worked for me was reading the text, and literally, line by line, hand crafting a flash-card that contains information I might be tested on. After creating my cards by reading and comprehending, I simply flashed the entire text out of order to myself in a series of cards and never stopped doing that until I answered every single one correctly. All day every day. Take them with you. Shit works. The last time I had to do this was for an industry certification for my job where supposedly only 18% of the applicants pass the test the first time. I was one of them. For more conceptual subjects like mathematics, the only thing that ever worked for me was solving extra problems and basically doing twice the homework assigned. If I did, I did ok. If I didn't, I just got by...or didn't in the case of Calc II a couple times in college. Oddly geometry was the only math subject I aced in my sleep, along with anything writing or science related.

Edit: To answer the main question though, it would be home repair. The house I live in used to belong to an old man that was especially handy. Everywhere I look I find functional built-ins he hand crafted to do a job. Work bench and vices in the garage...a wooden shelf with various hole sized drilled to hold his drill bits and tools...smaller work bench in the basement...a wooden storage rack holding all of the old window panes and doors from the house that he kept instead of discarding...loft beams and flooring in the garage for additional storage. Everywhere I look I see where his hand was, changing the structure in utilitarian ways. His ghost is showing me up in front of my wife every day while I'm still trying to hang that damn bathroom light fixture two weeks later.

It's interesting to see someone with this problem. I don't know where you're from, but many schools take it for granted that their students know how to learn because they see that students are learning some things. At the moment, there is the idea that "multiple intelligences" exist. I don't really care for that title because people are then prone to saying things like, "I'm intelligent in another way" which sounds like an excuse.

Anyway, the theory of multiple intelligences basically looks at learning styles. People take in, process and retain information in different ways. For example, some people learn well by listening and taking notes, or by reading about something or perhaps they learn best when engaged in physical activity. Perhaps you might think about how you go about studying and try different things. I bet if your instructor knew that you were actively doing something to try to better your understanding and your scores, then they would be supportive of that. Good luck!