joe f.

Khan Academy is terrible. Khan gives a complcated formula, which is fine, but Khan poorly or does not define what each variable—of several—means. Complicated formulae are easy, just plug in; but one has to say what each variable stands for. Khan is much too minimalistic, where one is puzzled how F01 is derived, "add all the scores," or "input the greatetst score," or, "average the scores." Instead, there is no defining the variables. Khan is ridiculous. Khan is no help for the SAT, for instance, because Khan is is trying to say in one sentence what requires six sentences.