Educreations allows you to create screencasts for free in the basic package. Educreations is accessible online. It seems to work just fine with a chromebook. You don't need to have an iPad to do it.
Use in the classroom:
- Create a screencast to explain a concept to the class. Share the link with the students via Google Classroom or your course LMS.
- Assign the students a problem and have them create a screencast and explain the concept to you. Remember, the have to understand the concept really well in order to explain it to others.
- Have students upload a photo of something being covered in class, for examples, a volcano, and have them explain what it does, what are the stages, etc.
- Assign each student a vocabulary word. Have them write out a sentence and explain it's meaning.
Here's my sample Educreation screencast.