I have been studying English for more than 7 years, from primary to junior high school, which leaves me a deep impression. The following ways are what i suggest. First, prepare the lessons ahead of time and mark the difficult words and phrase. Second, listen carefully in the class and take notes when necessary. Third, ask the teachers and other students for help in time if you have problems. Fourth, go over the lessons after class. Finally, grammar is so important that you have to get familiar with as much as you can. If you can obey the rules above, i am sure you will make great progrss in English!