An American teacher working in Beijing said: "In our summer course, we are having students post their own ideas onto Wikipedia. One student had already done this and his article about a ski resort near his home was published but marked as incomplete."
I'm sure students get a great thrill out of contributing to something that is as famous and internationally recognized as the English version of Wikipedia. But I can't help but feel it is irresponsible for a teacher to have a number of students do such a thing and violates the expectations of the people who go to Wikipedia for facts. If one student does it, it probably won't hurt anything.
By definition, English students are learning English because their English is not "good enough". They feel their ability to communicate in English is too poor. That's why they study English. Why is their English suddenly of the caliber to contribute to an encyclopedia? And why "their own ideas"? Wikipedia is not a blog. Just because they CAN do it does not mean they SHOULD do it. It would be better for them to write to some more informal areas of the web like actual blogs.
Likewise, a mailing list like TESL-L does not allow linguistics teachers to assign students to post here as a class project or homework. Without this rule, list members would become defacto teacher's assistants to a group of students in Morocco or some such place.
Of course, Wikipedia has different language versions and the students may do an excellent job contributing to one in their own L1. There are good places for students to practice and there are bad places for students to practice. Wikipedia was not designed as a practice venue for English students.