Oppia interactive tutor

most online lessons are still PDFs with a quiz bolted on; Oppia is closer to a tutor sitting across the table.

you build “explorations” — interactive activities that feel like a one-on-one conversation. students learn by doing, get feedback along the way, and contributors can ship lessons without waiting for a curriculum committee. i spent time around this project because the idea is simple and hard: education that responds, instead of education that broadcasts.

if you’re into edtech or open source teaching tools, it’s worth a look.