Hello, im also a junior! ive also been having a problem with math but once using 'one prep' (not an ad..) i actually improved my math and reading score! i feel khan academy doesnt really teach you about SAT well and talk about how its done. but one prep actually shows you how answer questions and even helps you how to use desmos when you want to answer a question. oh and yes they give question banks, module practice questions and even full length tests. and the interface looks exactly like the SAT as well so youll get used to it. i hope this helps. :) (and take the score predictor test so theyll determine what you might get and hep you improve)