The software, by Hi8us, has proved popular with some teachers, because its anonymity encourages shy pupils to come forward and allows groups to improvise scenes around difficult topics.
When Swanshurst school in Birmingham tested it, none of the pupils realised that Dave, who takes part in improvisations about bullying, and a waiter, who appears in a restaurant scene about Crohn's disease, weren't real.
The program developers are also adapting Dave so that he can cope with text slang such as MUSM for "Miss you so much".
Professor John Barnden, of Birmingham University admitted that Dave often sounded stupid, but said pupils found this liberating as it made them less afraid of appearing daft.
Hi8us developed the AI element in partnership with Birmingham University, and hopes to include it in publicly-available versions next year.
You can find a full version of Michael Shaw's article at www.tes.co.ukonline