I often hear students say that they "get it" in class but when they go to do their homework they draw a complete blank. Or similarly, a parent will tell me that their son or daughter does well on the homework but not on the tests. Both of these scenarios usually point to math being treated as a "spectator sport." It's easy to watch a teacher explain on the board how a problem is solved but until you actually "wrestle" with it yourself you won't build the mental math muscles needed when it comes to the test or real-life applications. So in addition to paying attention in class be an active listener and try and anticipate what the next step is while the teacher is explaining and if your hunch is incorrect use that to learn from. Most importantly, work the practice problems. Do the easy ones first but then challenge yourself by doing ones that look "impossible" to make you think and build those mental muscles. When I work individually with students I ask them how they would "tackle" certain problems. Then I may adjust the problem slightly and ask them what they would then do in the modified situation, etc. I will show some examples but I want the student to have the experience of it themselves and feel the anguish of defeat followed by the feelings of victory and success! So get off the bleachers and get into the game - you can do it!
Helping students succeed in math for over 10 years. Individualized attention makes the difference!