I've been told they can't throw as much information at you in a summer class versus a full term class. I'm probably retaking chemistry over the summer, maybe taking organic chem 1. Lots of people take them and do fine. Since it's basic algebra, I think you will be fine, and basic bio should NOT be that bad. As long as you think you can do it and you have the study skills to keep up with the pace, you should do excellent!