I'm a senior in high school currently taking AP Physics BC (mechanics) without having taken a physics course previously. I normally do well in my classes as I'm 10th in my class and am taking the most difficult level of classes I can. I can't say this for my AP physics class, which I currently have a 78% in. I'm genuinely trying and am not seeing any real results. What I have learned is that I need better resources to study for the class as a whole because my textbook doesn't really give me a lot of explanations or difficult questions to practice from. The difficulty of his (the teacher's) test questions really throw me off just because we haven't really done any questions like that in class. Also, the AP test review books don't really help either since they assume you have already learned the content. I approached him about this and he gave me this book called "Schaum's Outlines: College Physics" which contains a lot of practice questions on various concepts, which is helpful but I feel like I could find a better resource to study from so I don't have to waste 3 hours of my time consolidating and searching for resources to study from each time we have a test. So, my question: where can I find a good resource that has a variety of challenging questions to help strengthen my grade in my AP Physics BC (mechanics) class. When I say challenging questions I mean questions that help make you a better problem solver, cover various scenarios, but still stay in the realm of a high school class (questions that are difficult but can be solved with the knowledge gained from the class). So instead of asking what the kinetic friction given the coefficient and normal force, they ask what the kinetic friction is in a difficult case taking previously learned concepts into account and putting in more variables in -- like having 3 unidentical blocks together, connected by strings, each on platforms with different angles and having the front being pushed by a force with a 20 degree angle and having to determine the kinetic friction of each block, the acceleration of the system, and the tension in each of the strings. Sorry if that was a lot; I just wanted to give you a good idea of what I'm talking about :D. I apologize if this is in the wrong forum; I thought this was the most appropriate. I also appreciate any answers given and thank you for your time.