Next, we drew two “parking lots” with six school buses in each parking lot. In one lot, the buses were drawn close together. In the other lot, the buses were drawn far apart. Many of the students recognized that the six buses remain six buses whether they were parked closely together or parked far apart. A few students even realized and verbalized that the row of buses was exactly the same as the line of cubes. Although their arrangement changed, the quantity of buses or cubes remained the same.
On another sheet of chart paper, we drew six hoverboards and six school buses. (We tried to make the respective size difference obvious in the illustrations.) “Are there an equal number of hoverboards and buses, or are there more of one thing than the other?” Six hoverboards is the same quantity as six buses, even if buses are bigger.
Finally, we drew six hoverboards and five buses, again making the size difference obvious. The children noted that six hoverboards are more than five buses, even if buses are bigger.
A child’s understanding that numbers represent a quantity of items, and that numbers increase when counting forward, is very important. Conservation of number is a foundational skill. Our students realize that the quantity of item represented by a number does not change even if circumstances change. Bravo!