Mathematics activities in large classes: busy sky
Activity objectives:
1. Try to calculate the addition and subtraction of 7 according to the diagram.
2. Preliminary perception of the relationship between addition and subtraction.
3. Think from as many angles as possible and be able to speak your mind boldly.
Activity preparation:
1. Children's recording paper and pen.
2. Children's books, Volume 7, Page 3.
3. Flip chart (busy sky).
Activity flow:
(1) Beautiful balloon-see the addition and subtraction formula in Figure 7.
1. Teacher Shi Tu 1: There are two kinds of balloons floating in the sky. How many red ones are there? How many yellow ones are there? How many balloons are there?
Please list two addition formulas according to the number of balloons and write them on paper. (Guide children to put out two addition formulas related to pictures and meanings with digital cards. )
Please tell me how you listed it. (The child answers, and the teacher demonstrates the formula card. )
2. Look at the picture and list two subtraction formulas.
Teacher: There are seven balloons in the sky. Can you list the subtraction formula according to the color of the balloon? Guide children to put out subtraction formulas related to pictures and meanings with digital cards.
Please tell me how you listed it. Who else has different opinions? (The child answers, and the teacher demonstrates the formula card. )
(2) Lovely bird-a preliminary perception of the reciprocal relationship between addition and subtraction.
1. Look at the picture and list four addition and subtraction formulas.
The teacher shows Figure 2: There are a flock of birds flying in the sky. Please look at the differences between them. Can you look at the picture and list the addition and subtraction formulas?
Teacher: Please write the formula on the record paper.
Children look at pictures and calculate, and teachers tour to guide.
According to the children's answers, the teacher recorded four formulas in turn (2+5=7, 5+2=7, 7-2=5, 7-5=2).
2. Look at the four formulas and feel the reciprocal relationship of addition and subtraction.
Teacher: Did you find anything in these four formulas?
Encourage children to observe carefully, boldly describe their findings, and guide them to initially perceive the reciprocal relationship of addition and subtraction in the narrative.
(3) Complete the "Count a Number" on page 3 of Children's Book 7-see the addition and subtraction of numbers-column calculation 7.
1. Please turn to the third page of your children's book.
2. Children's observation pictures
Teacher: Count, how many birds are there on the picture? How many birds are there in the tree? How many birds are there on the grass? Please use this to list the addition and subtraction formulas according to three numbers and calculate them. How many addition and subtraction formulas can you list at most?
3. Children look at the picture (2-way addition, 2-way subtraction).
4. Collective communication and sharing.
Teacher: Please tell me how your formula is listed and why. (Guide children to perceive the reciprocal relationship of addition and subtraction. )
Did you make a list? Mark "√" next to the correct one, and correct the wrong one in time.