How to better introduce new courses?

First, the introduction of primitive cognition begins.

1. Introduce the old belt into the new belt.

"Mathematics is a discipline with strict logic and strong system." Like a long chain, the knowledge before and after is connected. Therefore, when teaching new knowledge, we should first review the old knowledge and draw new knowledge from the old knowledge, thus promoting the transfer of knowledge.

Case sharing: when we teach hundreds of millions of reading methods in the fourth grade, we can adopt the old-fashioned new introduction method. Because in the third grade, I have taught the reading of numbers within 10 thousand. Obviously, the reading of numbers within 100 million is based on the reading of numbers within 10 thousand. Therefore, in the introduction of the new lesson, the teacher can first show a group of numbers within 10,000, and let the students say the reading rules of numbers within 10,000 after reading. At this time, the teacher can ask: "Just now, we reviewed the reading method of numbers within 10,000, so how to read numbers greater than 10,000, such as five digits, six digits, seven digits and eight digits? Today, we are going to learn how to read numbers within 100 million.

Comments: Starting from students' original knowledge, reviewing old knowledge and introducing new lessons can achieve good teaching results.

2. Contact with life practice.

The new curriculum standard also clearly points out: "Life is a big classroom, which contains rich curriculum resources. Being away from life means that students will lose the other half of the course. " In terms of effectiveness, "education can only exert its strength through life and become a real education". Mathematics learning is based on daily life, and learning mathematics well is for better life and solving practical problems in life. Therefore, when designing teaching, we should make full use of this point to make the content of mathematics teaching come alive and bring students' life experience into the classroom.

Case sharing: In the second book of Grade One, "Two plus One (carry)", we can introduce new lessons through "shopping".

Teacher: Did you go shopping, children? Who will talk about some experiences and understandings of shopping? Name the students and express their experiences and feelings.

Teacher: This Sunday, our good friend Naughty and his mother went to the store to buy toys. Mother chose a toy from 24 yuan for Naughty, and a toy from 6 yuan to 9 yuan for Naughty. How can I buy it? Please choose one at the same table to see what different ways to buy; Calculate again, how much did * * * spend? (Students cooperate and interact according to requirements and prompts)

Comments: This is a computing teaching class. Most of the traditional designs directly show the problems to be studied, such as 24+6 and 24+9. Later, teachers often adopt the process of "letting students put sticks-discovering calculation methods-summarizing calculation methods". This design has no problem for students to understand arithmetic. But students are not very clear about why they want to learn this kind of addition, what they can do and what their practical use is. In the introduction of the above cases, the teacher designed a shopping situation that is close to the students' life experience and interesting to the students. In the process of solving problems, they first abstract mathematical models and then independently study how to calculate them, which can enhance the effectiveness of learning and improve students' learning enthusiasm.

Second, close to the introduction of new knowledge.

1. direct import method

Direct lead-in is a common method of introducing new lessons, which is often used in the teaching of many new knowledge.

Case sharing: When we were talking about decimal elementary arithmetic, the teacher wrote it directly on the blackboard: decimal elementary arithmetic.

Teacher: What do you think of when you see this topic?

Student: Elementary integer arithmetic.

Teacher: Think boldly, what do decimal elementary arithmetic and integer elementary arithmetic have in common in operation order and calculation method?

Comments: It is simple and effective to introduce new knowledge directly from the topic.

2. Doubt introduction method

Suspense can cause an anxious psychological state, with strong temptation and strong interest in exploration and pursuit. At the beginning of the class, teachers can reasonably and skillfully set suspense, fully stimulate students' curiosity, push students' thinking to the angry situation of "wanting to understand but not saying", arouse students' strong desire to learn new knowledge, and thus bring students into a broader mathematical world.

Case sharing: When teaching "the feature that numbers are divisible by 2 and 5", the teacher first writes a number "248", and then asks the students whether this number can be divisible by "2". After calculating, the student replied: "Yes!" . The teacher asked the students whether the number was divisible by "5". The student calculated and answered "No". Then the teacher asked each student to prepare a multi-digit number, first calculate whether it can be divisible by 2 and 5, and then test the teacher. Each student reports a number to see if the teacher can quickly judge which numbers are divisible by 2 and 5, which numbers are divisible by 2 and 5, and which numbers are divisible by 2 and 5 at the same time, without calculation. At this time, the atmosphere in the classroom is very active, and everyone seems to want to hit the teacher. But the teacher was surprised that the students could quickly and accurately judge whether the multiple numbers they reported could be divisible by 2 or 5. Then, the teacher further questioned: "Can you accurately see at a glance whether a number can be divisible by 2 or 5 without calculation?" The students shook their heads one by one and were stumped. At this time, mastering new knowledge has become students' greatest wish.

Third, the creation of situational import

1. Life situation introduction method

"New Curriculum Standard" points out: "The introduction of new curriculum should pay attention to students' life experience, choose things that students are interested in, ask relevant math questions, and strive to create' life-oriented' situations for students, so that students can start learning mathematics, experience and understand mathematics in vivid and concrete realistic situations. "

Case sharing: Teacher Huang Aihua introduced the lesson of "Percent Understanding" in Shaoxing in this way: "Students, what are the specialties of Shaoxing?" This problem is closely related to the local characteristics. Every student knows the specialties of his hometown very well. In the example, students mentioned that yellow rice wine is a specialty of Shaoxing. Teacher Huang immediately asked, "Is yellow rice wine powerful? Why? " According to the instructions on the label paper, the students pointed out that yellow rice wine is not very powerful because the alcohol content on it is only 16.5%. Teacher Huang immediately introduced, "Do students want to know what this 16.5% means? Today, let's take a look at the percentage. "

2. Story situation introduction method

The charm of the story is endless. Listening to stories has always been an important feature of primary school students. I wonder if you have noticed that no matter how naughty a child is, he will drop everything, stare big eyes and put on a focused expression that he may never have before, waiting for you to tell him a story. Stories can catch the attention of primary school students at the first time. They can make boring mathematics knowledge lively, interesting and fascinating, which is more conducive to activating students' thinking and mobilizing their learning enthusiasm.