The teaching goal of 1 in the teaching plan of "cutting cakes" in middle class mathematics.
1, let children try to divide an object into two equal parts in the operation process, knowing that part is less than the whole and the whole is greater than the part.
2. Encourage children to boldly try various ways and explore various bisection methods.
3. Speak out the operation process and results boldly to stimulate children's interest in dichotomy.
Teaching process:
The first is the story introduction, and the initial contact is divided into two parts.
1, enjoy the story "The New Biography of Stupid Bear".
2. Teacher: "If two brothers ask their children for help, how do you divide it?"? Now please let the children have a try? " (children's operation)
3. Teacher's summary.
Teacher: "dividing a shape into two equal parts used to be called dichotomy."
Divide the square in half.
1, try to divide the square.
Teacher: "If two brothers pick up a square cake, how can they divide it into two equal parts?" Now, please try the square and cut it. "
2. Children practice and communicate.
3. Teacher's summary.
Three, two equal rectangles.
1, divided into rectangles as far as possible.
Teacher: "If two brothers picked up a rectangular cake, how many different ways would they divide it?"? Please try it? "
2. Children practice and communicate.
3. Teacher's summary.
* * * Same as verification.
(1) Teacher: "Let's invite a child and see how he divides it?"
(2) Teacher: "How can we divide it into two equal parts? Just cut it along the crease and compare the two parts to see if there is a difference? " (The teacher talks about the operation)
(1) Teacher: "Who will tell me how you divide it?" ? Then how do you know if these two copies are the same size? "(cut off and compare)
(2) Teacher: "It turns out that there are two ways to divide a square, namely, edge division and diagonal division." (Show icon during call)
Junior Middle School Mathematics "Cake Cutting" Teaching Plan 2 Activity Objective:
1. Learn to divide the circle and the square equally.
2, can actively try to explore a variety of ways to divide the cake.
3. Stimulate children's interest in learning graphics.
4. Guide children to actively interact with materials and experience the fun of mathematics activities.
Key points and difficulties:
Learn to bisect a circle and a square; Explore a variety of ways to divide cakes.
Activity preparation:
Round and square operation paper, scissors, children's picture book.
Activity flow:
Let me recall the scene where I gave my child a birthday two days ago.
1. What did we taste together when the children celebrated their birthdays two days ago?
2. How are these cakes divided?
Second, learn the bisector of a circle and a square.
1. How to cut the round cake into two equal parts? Please come up and try it. After cutting, the teacher demonstrates the overlapping verification of two semicircles, focusing on guiding children to observe whether the two cut parts are the same size.
2. Divide the square cake into two equal parts. How to cut? Let individual children come up and score, and then let another child overlap and verify. Is there any other way to divide the square cake into two equal parts?
Third, children's operation exercises.
Divide into two halves on round and square paper.
Encyclopedia: Cake is an ancient western-style pastry, which is usually made in an oven. Cake is made of eggs, sugar and wheat flour as the main raw materials. Milk, fruit juice, milk powder, fragrant powder, salad oil, water, shortening and baking powder are auxiliary materials. After stirring, concocting and baking, sponge-like snacks are made.