Curriculum studies are basically about how grown-ups decide what kids should learn in school.
Imagine you've got a big puzzle with lots of different pieces. Each piece is like a different subject in school, like math, science, reading, and art. Now imagine that instead of you deciding where each piece goes, it's like the grown-ups in charge just give you a bunch of pieces and tell you to put them together without any instructions. That's kind of like what curriculum studies are trying to fix.
Curriculum studies is all about the grown-ups figuring out the best way to put all those puzzle pieces together so that it makes sense for you and your friends to learn. They look at different ideas about what things you should learn, what order you should learn them in, and how teachers should teach them.
Sometimes the grown-ups who decide on the curriculum will even ask kids what they think about it. That way they can find out if the puzzle they're trying to put together makes sense to you and if you're learning the things you need to help you grow up to be smart and successful!