Reading Incentive Program
I haven't tried this, but it looks interesting. It seems to combine some of the featurs of LibraryThing, but in a more sheltered environment.
Reading Rewards is a reading incentive program with a little something for all kids. Designed to encourage reluctant readers by rewarding time spent reading in various ways, Reading Rewards also has tools for eager readers who want to share their reading experiences in a fun, online community.