I have seen a lot of great ideas around the internet for tasks students can complete when they THINK they're finished. I poster-size charts like these and place them around the room. It really does cut down on the number of times I hear "I'm done, what can I do?" These tasks also give students great ideas for creating. You can really find out where some of your students' talents lie after they complete these tasks.
This is also a great template for using like a Bingo board. If your students complete 5 across, down, or diagonal, they could receive an incentive.
If you are interested in poster-sizing, Staples does a great job and they are very inexpensive if you ask for industrial prints. Good luck and have a great year. Please check out my other products.
Clipart by Creative Clips. https://www.teacherspayteachers.com/Store/Krista-Wallden