Directions: How many numbers are between 1 and 3?
Should one and three be included? What types of numbers are we counting? How can we figure out if there are any numbers between the whole numbers?
While students may initially guess 3 or 1 number, when they start including fractions, they should come to the conclusion that there are infinite numbers between 1 and 3 (or really between any two numbers).
Source: Robert Kaplinsky