After school, the teacher assigned a special math homework-making learning tools, and said that it is ok to do it according to the requirements of the second question on page 36 of the textbook.

I started doing it as soon as I got home. I took out my scissors and cut the cardboard into two disks, one large and one small.

Then determine the center of the circle, divide the circle into nine equal parts, and then write the nine numbers 1~9 on two circular surfaces respectively. Finally, find a toothpick to pass through the center of the circle and fix the two circles together. After I finished, I read the instructions in the book: turn around and say the product of multiplication of two aligned numbers. Every time you turn a grid, you can work out nine numbers. I started playing at once, turned around and said I would count to nine. After another round, I can form nine different multiplication formulas. This learning tool is really a good helper for me to recite formulas!