The Scratch team warns against submitting personal information to sites not controlled by it.

Your email address is required to join the Cutleaf Beta Program, which is in no way monitored or regulated by the "Scratch Team" at MIT. Unfortunately, there is no way for Cutleaf Beta to exist without collecting email addresses, as the service includes file sharing (scratch files). Email addresses provided for the Cutleaf Beta program will not be used for anything but the Cutleaf Beta Program Service, and will not be shared in any way.

 

However, if you are not sure you are willing to trust this site, then as a follower of the Scratch Team's community guidelines, I recommend that you do not join the Cutleaf Beta Program.