This activity comes from George Booker's book "Teaching Primary Mathematics"
In the early stages of our unit on probability, students were placed into mixed ability groups and given the following cards. Each card had a statement that could be made in reference to probability.
In groups, students had to place the cards on a probability scale in order from 100% chance to 0% chance. It was interesting to see their answers and how they interpreted the vocabulary on the cards. Especially "fat chance", as most students thought this meant a big chance. A great diagnostic tool as well.