The child can accurately calculate the method and tell his parents a long sigh of relief. We should let children learn methods and think, instead of pouring knowledge into their heads, taking out the composition of numbers within 10 and arranging them in a separate unit, and teaching the composition of these numbers based on the idea of division and combination.
There are three reasons for this arrangement. First, division and combination are important ideas, common methods to understand the objective world, and a strategy to learn mathematics. Students should master this way of thinking. The second is to teach the composition of numbers within 10 based on the idea of division and combination.
It is helpful for students to understand the essence of digital composition more deeply. The third is to teach the composition of the number within 10 with the on-off activity as the carrier, so as to provide students with opportunities and conditions for active exploration and memory.