I'd suggest considering going back to tech/startups, but trying to join one that's doing positive innovation in an important cause, like edtech or online education.
I'm glad you have the page in there, though! Best of luck with this project.
I think it'll be hard to work out what works just from that though, because the outcomes of education take many years and are often counterintuitive. You'd need to eventually do randomised controlled trials.
I've written some more here: https://80000hours.org/2015/06/5-reasons-not-to-go-into-educ...
I'd also recommend checking out sources like this: https://educationendowmentfoundation.org.uk/about/what-works...