My oldest really struggles with math. What I’ve decided to do is to go with whichever science lines up with her current level of math in the free curriculum guide. So for example, this year my 14yo DD is working through pre-algebra and General Science. Next year will be physical science and algebra. According to Apologia’s site, general science book is appropriate for grades 7-9, so I don’t think we’ll have any problems with this…and the math shouldn’t slow her down.