I have a box in my classroom called the "I'm finished box". It is where I put all the extra copies of worksheets (from when I make too many copies, or when the kids are off sick) that would otherwise just get thrown out. It is amazing how much the kids like to go through this box and redo activities that they have already done. If it gets a bit low on sheets (although it never seems to - I guess I need to photocopy less
) I just chuck in a few dot to dots, or colouring pages as those skills are essential at this age too.
oh and I forgot to add that all sheets from this box MUST be taken out of the classroom at the end of the day. As they are essentially practice activities I dont want them hanging around in the classroom for days!