My DS 12 recorded a 272 math this fall. While he very much enjoyed the fact that the test moved with him and has resulted in some very positive and much needed subject acceleration for him, he was able to reason answers that he yet needs to cover in depth in cirriculum. An example is that he reasoned through some trig questions by process of elimination and has not yet studied trig. Sure beats making a silly arithmetic mistake on a set 40 question test and being assessed that way.