Observe whether the change is regular. First of all, children need to observe carefully and have an analogy and a constantly revised thinking process. It must be very confusing at first, and there needs to be a familiar process from basic questions to improvement questions.

Rule 1: The sum of the digits in the unit and the tenth digit is equal to the number of disks. Rule 2: The number of pendulums is more than the number of wafers 1.

Find the rules to exercise children's observation ability, and then exercise children's observation ability. If you can understand the topic yourself, find the rules, and then whether you can understand the topic yourself.