Teaching content: How much (two digits times one digit)

Teaching objectives:

1, master the oral calculation method of multiplying two digits by one digit, and go through the process of various algorithms to calculate correctly.

2. Understand the meaning of multiplication and solve simple practical problems with multiplication knowledge. Cultivate students' abilities of observation, analysis, reasoning and generalization.

3. Through group cooperation and communication, cultivate students' cooperative spirit and innovative consciousness, and feel the application of mathematics in real life. Improve the ability of mathematical communication and experience the fun of mathematical inquiry.

The focus of teaching is to master the oral calculation of multiplying two digits by one digit.

Teaching difficulties: two digits multiplied by one digit (carry) oral calculation.

First, check the import.

1, show me the math problem.

2. The courseware shows the situation map, and the dialogue is introduced: On Sunday, naughty, laughing and playing with their good friends at the seaside. In the shop near the seaside, they bought a lot of things, and they want to ask everyone to help them calculate. How much will it cost? Would you like to?

How much does it cost to write on the blackboard?

Second, explore cooperation and exchange reports.

(1) Explore the multiplication method of multiplying two digits by one digit without carrying.

1. Guide the students to observe the pictures. What mathematical information can you find from the picture? (Identify each swimming ring 12 yuan and each ball 15 yuan).

2. Analyze the mathematical information, put forward the questions you are most interested in according to this information, and communicate in class.

3. The teacher leads to the key question to be solved: "How much does it cost to buy three swimming rings?"

4. Explore "How much does it cost to buy three swimming rings?" This question. Students use their favorite methods to calculate.

(1) Teachers guide students to think independently according to problems and list multiplication formulas: 12×3 or 3× 12.

(2) Communicate their own oral calculation methods and give feedback. Teachers use different algorithms to encourage students.

(2) Explore the method of multiplying two digits by one digit (teaching difficulty).

1. How much does it cost for students to buy 1 kayak independently by their own methods?

(1) List the formulas independently and try to solve them.

(2) Share your oral calculation method at the same table, and then report.

(3) Guide students to talk orally about how to multiply two digits by one digit.

3. Practical application, expansion and extension

1, show the basic exercise (exercise 3).

(1) Let students calculate independently.

(2) Take a few questions to talk about the oral calculation method, and the teacher will give timely guidance.

2. Solve practical problems.

(1) Students solve the first small problem independently and then organize communication.

(2), the second small problem.

First, students discuss at the same table.

B, then report to the class and encourage students to say different ways of thinking.

3. Fill in the form.

Let the students fill in the form independently first, and the teacher pays attention to the guidance and help for individual students to fill in the form, and then feedback and exchange.

Four. abstract

What did you buy today?