If you want to use Seesaw in more than 10 classes at a time, you can check out Seesaw Plus. Among other great features for assessment, Seesaw Plus users can have up to 25 active classes at a time. Here’s more information about Seesaw Plus: http://web.seesaw.me/seesaw-plus.
If you’d like to use Seesaw in more than 25 classes at a time, Seesaw for Schools is right for you. Using Seesaw for Schools, teachers can have up to 100 classes at a time. http://web.seesaw.me/seesaw-for-schools/.