Kubbu is an amazing new site that I learned about from the equally amazing blog, Websites of the Day (by Larry Ferlazzo - who has a new book out which I hope to review soon!). Kubbu reminds me an educational CMS (content management system) similar to Moodle, but much more simpler.
Kubbu is a site where teachers can register (for free) and sign up to 30 students. What makes this so great, is that the students do not need an email address to sign up, the teacher can do that form them w/ registered accounts (think Glogster). It is this educational "portal" which makes Kubbu ideal for an educational environment that has to abide by CIPPA compliance.
Teachers can use Kubbu to create: games, quizzes, and crosswords. They can create up to 15 activities that will be stored for 30 days.
I highly recommend giving Kubbu a look by clicking here.
Below is my crossword example...