Melissa,
Since your daughter�s interest is biology, maybe it would help to suggest the textbook that my daughter�s 10th grade class uses which her teacher says is commonly used for AP Bio. The course does seem reasonably strong, as the average grade so far is a C.

Biology Concepts and Connections by Campbell

I do not know yet which textbook her school uses for AP Bio but the current 10th grade class is a prerequisite for the AP biology.