When students graduate to book 2, I usually give them a review chart to help keep their book 1 songs rehearsed. Songs like Etude and Gossec Gavotte can be completely forgotten if you don't practice them at least once a week!
Here's a link to the chart I use. There's also a link in the side-bar under "links for my students". The document is a pdf and the link will re-route you to adobe acrobat where you can print off the chart for yourself. USE IT! PRACTICE :)