As far as I'm aware, the #1 education startup was created by someone who was poorly versed in the "science" of education.
He seems to be improving things with science now, but that's a fairly recent thing.
If you're talking about Khan Academy, they're a non-profit not a startup.
Also, he had several funding offers from VC's, so your assertion about what VC's might fund is incorrect.
I think it's important, especially with startups, to look to the future rather than to sit around judging the present.
In the beginning, Microsoft were making a limited Altair BASIC that only appealed to a handful of hardcore geeks, but later they had a computer in every office and home. You don't get there if you try to solve the world in step 1.