It's effectively a commertial program that duplicates the Khan Academy nitch with practice problems and video explanations. Contrary to Khan, it's aligned to standard curricula by grade level.
All answers are multiple choice, and you need to get ten right to get credit. We found multiple errors in the answers (6x4 is not 26 last I checked...) that caused some frustration. The content was covered at a very shallow level, with little stretching necessary. We saw no problems requiring a two-step solution.
I wouldn't pay for it if I were just looking for some enrichment. It might be ok for drill for a child with some gaps and weaknesses.