Overall, 71 percent of students reported that they liked using Khan Academy and 32 percent said they “liked math better” after using the tools. Eight in 10 teachers reported they thought students were at least moderately engaged when using Khan Academy, although usage varied widely depending on the school or classroom. Some students said Khan Academy encouraged them to learn independently, with 45 percent reporting they were able to learn math on their own without it. We contend that the videos at Khan Academy are alarmingly devoid of PCK. We claim further that (1) the examples Khan chooses appear selected at random and thus are, perhaps unsurprisingly, often quite poor. They are prone either to create further confusion, or to fail to address fundamental questions students are likely to have; and (2) Khan’s explanations are frequently off target in addressing likely student questions that experienced teachers would anticipate and elicit.