This is a great activity to get students thinking about what Whole Numbers and Integers really are. I was surprised when I first used this activity at their lack of true understanding.
Three sets of 12 numbers are given. Make copies and cut cards. Students pick cards and decide if the number is a whole number, integer, or neither. They write the number in the correct place on their VENN diagram.
This can be used as a formative assessment. A key is provided for each of the sets.