This is an effective program that I've been using for my class! It is easy to use and you can use it on your computer and or your phone! 
What is Class Dojo?
ClassDojo is a communication app for the classroom. It connects teachers, parents, and students who use it to share photos, videos, and messages through the school day. They use ClassDojo to work together as a team, share in the classroom experience, and bring big ideas to life in their classrooms and homes.
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