How I Use It
I've used this in my high school math classes. I first set up google accounts for each student.
I have found it very helpful to direct my students' learning (some will just spend all of their time on something like adding integers if I don't). We cover a topic in class then I tell them which things on Khan to practice. During class I walk around and check to see how they're doing, helping when they need it. After class I can then go in through my account and review their work.
I've seen my students take to this program in a way they rarely do with other apps we've tried. They really enjoy completing pieces of their math universe. The teacher/coach side is also evolving into a very strong assessment piece for the teacher to see what students are proficient with and where they are struggling. I am interested to see how the new diagnostic exam at the beginning works out.