levette - There are very good SDA schools. However, some do lag behind academically. It just depends on the specific school. For example, I attended Pine Forge for one year, and the academic program needed work. On the other hand, my understanding is that Spencerville SDA Academy in Maryland - closer to my area growing up - is very good. I would go for the day schools before the boarding academies.
Most importantly, however, is spiritual education. The benefit is immeasurable. Honestly, when I have children, I will first look for a decent SDA school if we can afford it. Children receive sound Biblical instruction, education without Sabbath conflict and usually become part of a lifetime spiritual family.