One more thought: a lot of these issues (word problems, decimals) are covered in early chapters of AoPS pre-Algebra too. Although AoPS almost certainly won't use the same language, it is really good at showing *why* things work, not just what, and how to come at them from multiple approaches. Possibly if your DS got that deeper understanding of the underlying math, it would be easier to translate/ apply/ recognize how to deal with the problems, regardless of the specific language and processes used in his class?

The AoPS pre-algebra book is worth having just as a deep intro to almost everything; however, there are also lots of free videos that cover all the concepts, if not the depth: http://artofproblemsolving.com/videos/prealgebra

ETA: Really, AoPS doesn't pay me for all these endorsements. But they ought to. smile

Last edited by Platypus101; 10/20/15 08:07 AM. Reason: Honest, I'm not a shill