Measuring ruler: take a long board and mark the ruler measurements - place on any wall and mark the kids growth. (Good way to take the memories with you even if you have to move because it can go on any wall!!!! :)
Put their first pair of shoes in a shadowbox and hang in their room. Use velcro on the backs to make them stay. Note to self: Shodowboxes can be found at Michaels. Something to do with all those adorable shoes! Maybe her first dress?