Posters?

No, not all of you who comment (and thanks btw!), I mean posters for my classroom which is pretty bare. I've been contemplating having the students make posters dealing with math to put up in my room. There is some upside to this, it'll be a welcome change for the students, and it would add some personality to the room, but I have serious reservations about this.

1. 6th period. I seriously doubt that they'd be able to handle this assignment. Too many kids that would rather talk and disrupt my class.

2. It cuts into valuable class time. This kids are so behind it's not funny, every day is needed just to get my students to even be close to caught up.

3. Would they actually learn anything? Or would this just be a wasted day?

Any ideas?