勉強 （ベンキョウ） study, diligence, working hard, experience, lesson (for the future), discount, price reduction

勉学 （ベンガク） study, pursuit of knowledge

猛勉 （モウベン） studying hard, cramming

のこ勉 （ノコベン） staying behind after school to do private study

努める （つとめる） to endeavor (to do), to endeavour, to try hard, to work hard, to strive, to make an effort, to exert oneself, to devote oneself, to be committed (to doing)