There is a new teaching tool that uses "the most current understanding of how the children learn" to provide instruction as to how to best improve the learning of every child on an individual basis. That's the claim. Here's the link to a much fuller explanation of how this works. It takes a lot of work/child to set up the initial assessment, but then has a number of teachers who are singing its praises.
Oh, and it's $15/child/year.
If it works, I'd say that it is very much worth it. However, I can't see a high school teacher using this for all the students.