https://insertlearning.com/

DocentEDU/InsertLearning is an exciting new app and browser plugin that essentially lets you turn any webpage or online document into an engaging, interactive, digital lesson...
With the tool, you can easily add questions, discussions, notes, and HTML widgets into an already existing webpage, and send it out to your students or classes...

Watch the overview video here:
https://youtu.be/UPmJiK5em1Q

http://simitator.com/generator/twitter/tweet

Possible class project, have students build fake twitter tweets and chats.

Website also has tools to make fake Facebook and YahooAnswer posts.

https://edu.google.com/k-12-solutions/classroom/
Google Classroom is the ideal platform for teachers to share everything their students need for class in one place. Teachers can post classroom assignments, quizzes, YouTube videos, anything that is connected to the Google Apps for Education.
Teachers can contact parents from Google Classroom. Teachers can grade assignments. Teachers can even copy and paste assignments from class to class.