As the Halloween season begins, let your students play a spooky game. How does this work?

Students can play this game online at Ghost Whisperer Crystal Ball and then

- Figure out why it works.
- Construct viable arguments
- Critique the work of others

This activity can be used with any grade level elementary through high school. Younger students might work with patterns, multiples and order of operations. Older students might work with systems of equations to prove how the Ghost Whisperer works.