Research before Coding !
Upon reading Free Software in education my first tought , and actually a general tought not aimed at Arnaud, was.. why would one want to write Yet Another version of a Tool or piece of code that is already available in Open Source, did they forget to google to see what already exists ? Are they just egotripping coders who want to say .. "Its MY project" , Is the other one written in "the wrong technology".
There is so much new work out there that we really don't need to spend time on duplicating stuff that already works.
But just to clarify .. Arnaud is doing a great good job teaching people about Open Source and code in general in this project was to teach people stuff so the most important part is that they have learned something new, and such a project is reasonable in size and feature set to do as a teamwork and show people the ropes. But a lot of other projects make the mistake to just start writing code and not look around hence wasting valuable time they could spend on new developments.