This blog post is full of amazing ideas for how to prepare for Open House night and get a head start on learning about your students! I especially love the idea of an “About the Teacher” page and a page letting parents know all of the awesome things their children will be learning that year.
Snowball Fight...kids write 3 things about themselves on a sheet of white paper. They do not write their names on the paper. Wad it up and on your command, have a "snowball" (or baseball) fight. At the end of 1 minute, each student grabs the nearest snowball and tries to guess who wrote it. Would be great at the beginning of the year!