Xiaoming has some fruits, including 4 apples, 3 pears and 2 bananas. How much fruit does Little Yi Ming have?

Analysis: This is a question of classified thinking. We can divide these fruits into different groups and then add up the number of fruits in each group. For example, we can divide apples, pears and bananas into three groups, and then calculate the number of fruits in each group respectively. Apple group has 4 fruits, pear group has 3 fruits and banana group has 2 fruits. So, Xiao Ming has nine fruits.

2. There are some numbers, including 3 even numbers, 2 odd numbers and 1 zeros. What's the sum of these figures?

Analysis: This is also a question of classification thought. We can divide these numbers into different groups and then add up the numbers in each group. For example, we can divide even, odd and zero into three groups and then calculate the sum of each group of numbers respectively. The sum of the numbers of even arrays is (2+4+6)= 12, the sum of the numbers of odd arrays is (1+5)=6, and the sum of the numbers of 0 groups is 0. So, the sum of these numbers is 18.

3. There are some animals, including 2 cats, 3 dogs, 1 rabbit. If each cat weighs 3 kilograms, each dog weighs 5 kilograms and each rabbit weighs 2 kilograms, what is the total weight of these animals?

Analysis: This is still a question of classification thought. We can divide cats, dogs and rabbits into three groups and then calculate the total weight of each group respectively. The overall weight of a cat is (2*3)=6 kg, that of a dog is (3*5)= 15 kg, and that of a rabbit is 1*2=2 kg. Therefore, the total weight of these animals is 23 kg.

Application of classification in primary school mathematics;

1, highlighting the idea of classification, and initially gaining a sense of classification.

Psychologist Bloom believes that setting goals is to facilitate objective evaluation, not to express ideal wishes. In life, primary school students have a certain sense of classification, such as gender classification and age classification. Therefore, students can easily accept the application of classification in mathematics.

2. Understand concepts by classification and grasp the essence of mathematical concepts.

The formation of concepts often begins with classification activities. Therefore, introducing new knowledge through classification in teaching is conducive to students' understanding of concepts. For example, how to define the common geometric figures in life, such as quadrangles and pentagons? Usually, according to how many line segments make up a closed figure, they are polygonal.