Planning a party
This would be the best project for my class due to the fact that we are currently reviewing the future with "going to"; therefore,, planning a party (that could even take place, why not) is a great way to make real use of the target language. The four skills would be practiced throughout, with special attention to the written part when elaborating the invitation, perhaps.
What other kinds of projects have you (or other teachers you know) done?
I have not done projects as I usually teach teenagers and adults. A teacher I know, had the students elaborate their own masks for halloween, but I am not entirely sure about what she was teaching nor the procedure behind.