O and I had fun reviewing her shapes using these shape windows (via Confessions of a Homeschooler).
I printed the shapes on cardstock and used an x-acto knife to cut out the middle of the shapes before laminating them. After laminating the shapes, I cut them out of the cardstock (I like to do most of my cutting after laminating in order to have a cleaner edge). Now they look like windows, which is a fun effect :) O had fun running around the room and looking at different objects through her shape windows, and she's looking forward to using the shape windows to teach "baby sister" her shapes!