This is a good article about using teachable agents to help learners with writing skills. Learning by teaching, or using teachable agents, has been around for some time.
What is a teachable agent? Thousands of years ago philosopher Lucius Seneca stated, “We learn by teaching”. This idea evolved to the modern educational theory called “Learning-by-Teaching”. It has been widely observed that when students teach their peers they learn much better than they learn for themselves (Allen & Feldman, 1976; Gartner, 1971) since they no longer passively receive knowledge from teachers. They are performing as tutors to actively master the content. The success of this method led to a new type of pedagogical agent, the Teachable Agent (TA), in 1990s. Teachable agents are computer agents that allow students to teach and improve their own learning (Biswas, et al., 2005).