It seems to me that you are simply being very thorough in your study habits. That is merit-worthy. Not sure why you feel you are being shady. Unless you are writing all the questions and answers on a cheat sheet that you are taking into class, what you are doing seems perfectly legit to me. If the teachers are using readily available test mateirals, that’s not your issue.
You should check out Haverford and other colleges known for their honor codes:-)