Somewhat off task for a teacher of history yet this article written by Dean Giustini in BMJ describes the evolution of the semantic web in a clear manner. Dean references Sir Tim Berners-Lee and his work on the semantic web. The article includes a brief yet useful glossary and a comparative table that lines Web 2.0 up against Web 3.0.
As you read the article replace the word ‘doctors’ with ‘educators’. Terms such as ‘medicine’ and ‘health-care’ can be replaced with terms such as ‘teaching’ and ‘classrooms’.