This activity can be used with any subject matter you are studying. It provides an excellent means of integrating mathematics into any subject. However, when he asked them to show the quantity of rice needed to feed a certain number of people, they could readily determine the bowl size needed to hold the uncooked rice. His conclusion was that numbers and the ability to use numbers comes from our culture and how our culture uses numbers. I suspect that Micronesians are good at guessing tide tables, quantities of food for fiestas and severity or closeness of typhoons.
Prior experiences play a big role in our ability to estimate.
We should give our students many opportunities to use estimation.