I wasn’t brilliant at physics at secondary school. I managed in class, though, with the help of my peers which you could call social learning. Pre-internet, that social network was confined to the real world – and occasional phone calls. Homework wasn’t generally a topic of conversation but I don’t think I had anything like the 2-3 hours school children can have today. On one occasion, my homework included a question about light refraction and where a fish would appear to be to an observer from the surface as opposed to where it actually was. I couldn’t answer, so I just wrote “Don’t know” and handed it in.