noun, noun or participle which takes 'suru'
studying like crazy; cramming intensely
Slang expression for studying obsessively or grinding through study sessions, often with a negative or self-deprecating tone.
試験前は毎日くそ勉強してる。
Before exams, I'm studying like crazy every day.
あいつ、くそ勉
Apparently he crammed like a madman and got into Tokyo University.