Idea #1--Write letters for the next school year. I had my students write letters to themselves about things that might want to know or be reminded of on the first day of school when going into the 4th grade. These students really blew my away with some of the things they came up with. We put the letters into envelopes and decorated them. They will be able to open them the first of the following school year.
Idea #2--An alphabet memory book. My students are in the middle of creating an alphabet book that contains information that we have learned correlating with the letter it begins with (A=addition, c=clouds).