Great question. Here’s a video description that explain the main differences. The short answer, though, is this:
- Saxon Math 3 and Intermediate 3 are fairly different
- Saxon Math 5/4 and Intermediate 4 are 90% the same textbook
- Saxon Math 6/5 and Intermediate 5 are 90% the same textbook
- Saxon Math 7/6 and Course 1 are 90% the same textbook
- Saxon Math 8/7 and Course 2 are 90% the same textbook
- Course 3 and Algebra 1/2 are completely different textbooks
The School line (Intermediate 3,4,5/Course 1,2,and 3) have more word problems and logic-based questions to meet Common Core Standards.