The percentiles problems illustrate one of the difficulties I've had with Jared when trying to cover certain basic principles of Statistics. He is under the impression that he has the subject under control, so during lessons he can sometimes be a tad uppity, and say he knows the topic so why should he waste his time learning it. I will persevere, and try to explain it, but I can tell I don't have his attention. But, when testing time comes, Jared ends up being a bit clueless. However, to his credit, when confronted with the test situation, he does try to absorb the (re)teaching a bit more - I'm not that interested in a cold grade, I'm more interested in the fact that he knows the material and hence will cover it again. In these situations, I always try to gently point out to Jared that life will be a tad different at university, and that it might be to his advantage to pay attention to his lecturer.