Answer:
Mine is time management.
Explanation:
Two years ago, I entered middle school. There was much more homework and I took much more extracurriculars, but I was a slow worker and thinker. At the same time, I also wanted to continue having free time for myself.
At first, I always gave myself free time before I even finished my homework. I would get enchanted by all these videos and before I realized it, it was 9:00pm and I hadn't done any homework. Then I'd have to finish my homework, and there was no one to ask for help when I had problems, since everyone was asleep. Not only that, but I slept really late (like 1 am) and I took zero period pe, so I had to wake up at 6 am. One cannot survive with only 5 hours of sleep.
Now, I write out a schedule for myself everyday. It helps a lot. I sleep at 9pm now, I get all my work done, and most importantly, I still have free time to spare.