An FYI, I went to Catholic school too. I spent years in theology classes and left feeling like I knew next to nothing about christianity. I hated theology class and barely passed all of them. I learned a lot by voluntarily partaking in that bible study. What I learned was that the christians (or any religious person) that I liked were the ones that admitted that they didn't know squat but liked the teachings of Christ. The ones that are scary are the ones that have it all figured out and know unequivocally that they are saved and you are damned. Those people (from any religion) are to be feared.
My religion classes in high school were mixed. I really enjoyed class on scripture and social justice while I didn't particularly like sacrament. It more had to do with the teachers than the material in all honesty.