Grammatical structures and concepts could be a part of a project, but as a by-product of the project, not the main point of it. In a World Language class, we might ask the students to write a story or a comic strip, for example, and in order to write the story, they would have to demonstrate that they can use appropriate vocabulary and linguistic structures, such as the preterit and the imperfect for narrating past events. However, the project would NOT be about the various past tenses - they would be tools to telling the story. I might do a workshop on how the language of the course works - how we structure sentences in passive voice vs active voice, and what the differences are between each kind of sentence - to support students in their writing, but not as an end in itself. What do you all think?