In a couple days, i have a science test and I know what I am doing but how long should i study?. Their is a bit of stuff you can review but some of it you cant. Our teacher told us to look over the questions he gave us to see if we are doing it right, but my problem is not that, its how long I should study for. Until i understand, but that problem is if i understand in an hour my parent6s are going to tell me that i did not study enought. What should i do.?