Some of these are amazing, and not all as ridiculous as they might seem at first glance. At least half a dozen of the entries are almost fully realised in the form of an iPad and a handful of apps.

Every generation has its shiny new technology that's supposed to change education forever. In the 1920s it was radio books. In the 1930s it was television lectures. Here in the second decade of the 21st century, it seems the Massive Online Open Course (MOOC) is the education tech of tomorrow. Let's hope it pans out better than previous attempts.

Today we take a look back at 15 technologies that were supposed to radically change the way that people are educated around the world. Some innovations were mostly hype. Others had an undeniably meaningful impact.