moving target
1, guess and confirm the number of oranges, and accumulate preliminary experience in estimation and different counting methods.
2. I like to observe familiar things in my life and I am willing to express my opinions.
Activities to be prepared
Several oranges of different sizes, plastic baskets, pens and statistical tables.
Activity process
First, compare and discuss the number of oranges.
1. Observe and compare the sizes of oranges.
Do you like fruit, children? So what kind of fruit do you like to eat? Oh, that's good, isn't it? I like xx fruit, too. Today, the teacher also brought a fruit. Let's see what kind of fruit (orange) this is. What's the difference between them? (A big one) Ah, you all know it without asking.
2. Compare two baskets of oranges of different sizes.
The teacher brought not only two oranges, but also two baskets of oranges. Look at these two baskets. Are they the same? What's the difference between oranges in the basket? Do you think the big orange holds more or the small orange holds more? (Children talk nonsense) Then let's check and count, shall we?
3. Count and verify the number of oranges.
Count what is big first, and you count it (the teacher takes it, and the children count it). Could it be wrong? Let's count again, shall we? Now let's count in another way, two by two, and start counting. Remember it's eight o'clock.
Now let's count the little oranges. I will ask my children to count up, then let them count down, and finally count silently. What does it mean to count silently? How many small oranges are there?
4. Discussion: Why are there different numbers of oranges in the same size basket?
Now children know whether there are many big oranges or small oranges. Why are there more small oranges and less big oranges in the same size basket? (Children tell) Because small oranges take up less space, they can hold a lot more.
Second, guess and record the number of oranges.
1, guess whether there is so much pulp in the orange peel? How many tablets may there be in each tablet?
We have to test everyone again. You said this orange was peeled. What's inside? You are so smart, so what does this pulp look like? A chess piece, such as the moon. ), I also want to ask you, who has more pulp in this large and small orange? Is it? How many slices will there be in a big orange and how many slices will there be in a small orange?
2. Record the guessing results.
Let's guess. Then the teacher wrote down your guess. Let's guess which orange is bigger and which is smaller first. Before guessing, the teacher secretly tore a piece to see how big the pulp is, so that we can accurately estimate how many pieces of pulp there are in the whole orange. Look, the teacher began to peel it a little. Ok, now please guess how many pieces of pulp there may be (and then observe the small orange)
Third, check the pulp quantity of large and small oranges.
So how many pieces of pulp do large and small oranges have? Do you want to peel it off and count it? Put them in the basket. After peeling, think about how you count and how many pieces there are. Let's start now. Everyone chooses an orange.
Fourth, the method and result of communication number.
1. Have all the children counted? Now, please come to the front and count. How many pieces of oranges do you have? Are they big or small? Let's have a look. It really is 12. Write it down quickly. Is it big or small?
2. Are there any different methods? First, pull the oranges in half and count them around. What if I can't count it? Find a spot.
Summary: Now let's see if there are more big oranges or more small oranges on the record sheet. Can you tell? Oh, irregular. It turns out that there is no necessary relationship between the amount of orange pulp and the size of orange.
Fifth, extension.
What other fruits are juicy in daily life? Teacher, there is a big glaze here. Think about how many pieces it might have. Ok, let's peel it off and count it after class.