How I Use It
I have used Khan Academy Chemistry 1 and Chemistry 2 with my high school students. It is very effective for students missing lectures, those who need a second chance at material introduction, and to leave as part of my lesson plan for a substitute when I know I will be out (as it is difficult sometimes to obtain chemistry certified substitutes). I also use a modified flipped classroom style of teaching and these videos can be used as part of students' homework assignments. The only negative I have is that they are lengthy for flipped classroom use and students consider them a bit dry.
My overall opinion of this product is very favorable. The different colors Sal uses in his teaching are helpful for visual learners and the way he explains/breaks down difficult concepts is usually excellent. A wonderful tool for introducing a concept or remediation - just wish the length was a little shorter.