One thing we love to make in our house are sugar cookies. They taste great they are easy to make and the kids love helping! Years ago I found a small pastry dough roller, Isabella loves using it and it is very easy for her to handle.
TIP: If you want to ensure all of your cookies are the same depth. Add a few rubber bands to each of the ends of your roller and you will then ensure that you always roll out to the same depth!