We love, love, love the Student Guides! I find the TG very useful too. We started Aristotle in grade 5 and used it in tandem with some of the Stop Faking it books, GEMS guides and an AIMS guide as well as lots of documentaries and Brainpop. We are almost finished with Newton and while I had every intention of using the Stop Faking It books again, we don't have time and instead use Adaptive Curriculum, docs and Brainpop. We also took a side trip back in time to the Renaissance using an Interact Guide and Google Earth.I think a lot more is retained when you do the actvities and experiments in the SG. We use the SG as a scrapbook, putting all we have done related to the chapter in it. We just pulled the Aristole SG out yesterday because we were watching something where Hero was mentioned and we remembered that he was featured in our book. I think there is a lot of science in Aristotle; astronomy, scientific method, simple machines, density and buoyancy. Lots of math too!