I think we're learning the limits of screen-based education now. There's something about being in the same room with a person at a chalkboard that is far more effective - at least anecdotally. (I'd be surprised if there wasn't research backing this up). And this seems deeply unfortunate if true, because it means the cost of learning can't go all the way to the ground.

Two thoughts: Africa can’t afford in-person teachers. The ones in my country are not great on average.

I couldn’t learn maths in class. Too distracted, too annoyed with stupid questions. But I increased 3 symbols in 3 school terms with a slide projector and audio tape, where I could focus and rewind. Teacher there was for bits I didn’t learn from the slides. I’m probably in the minority but I’m sure there are more of me.

Digital education catches kids like me and kids who have no access to excellent educators. And marginal cost is zero, so no harm in giving access to the world.