Group lesson items by grade level - I have adopted this idea this year, and it is working well. I also keep a file folder for each grade level in the front part of a tall filing cabinet. It contains teacher notes/lesson details for the month.
Teaching pitch: DIY Turn PVC pipes into a playground musical instrument. I wish this had the instructions with it, but I might be able to figure it out. This might even work as a service learning project for my daughters' school.