Understanding of divisor. The students in this unit have little contact in life, but now the students are very smart and lovely.
Rich in extracurricular knowledge,
Such as challenge data,
Although these big numbers are abstract,
It's hard for students,
But they are very willing to accept the challenge.
The new curriculum standard clearly points out that in mathematics teaching, teachers should make full use of students' existing life experiences and design vivid and interesting life experiences.
Education and teaching activities to stimulate students' interest in learning. In the teaching of this unit, census, land area, production
Total value and other data, so that students have a high interest in learning and strong learning atmosphere. For counting, I strengthen the meaning of students' logarithm.
Understand. Let the students count the small squares by hand, and then combine the multimedia demonstration to give them an intuitive perceptual understanding: how many are there?
How big is 1 million? Then, with the help of counter, we can master the numbering method of large numbers, understand the composition of numbers and deepen the concept of logarithm.
Know the number sequence, number of digits, level, counting unit and the ratio between two adjacent counting units.
Students can discover, experience and understand by themselves. When students have a preliminary understanding of large numbers, I will organize students to accept them.
Collect some big data,
Talking about the practical significance of these data,
Improve students' feelings about large numbers.
At this time,
"Numbers"
It is no longer boring and mechanical, but very close to students' daily life.
This unit combines multi-digit reading and writing in teaching, because these two aspects are an organic whole.
Body. The difficulty is to read and write large numbers with zeros in the middle. I let students get confused in reading and writing, and then guide them.
With the help of the learning experience and foundation of Reading and Writing within 10,000 people, this paper discusses and summarizes the reading and writing of Zero. And in
In the teaching of rewriting large numbers,
I use data collected by students,
By observing and comparing, I realized the necessity of rewriting large numbers.
Make love. Data rewriting is a change in data representation, and its size has not changed. I noticed in the process of rewriting.
Explain to the students why they should write the counting unit after rewriting.
such as
9600000=960
Wan,
The number to the left of the equal sign is
In units of "units",
Counting units are generally not written in units of "one". On the right side of the equal sign is "ten thousand"
Unit, if you don't write this counting unit, it will become "A" as the unit, so there will be a difference between the two.
It's huge. This kind of explanation and emphasis will help students make fewer mistakes in the follow-up exercises.
The divisor is a number that is often used in daily life.
It's different from the exact number,
Represents only a specific range of objects.
Students often come into contact with approximate figures in their daily activities.
It's just that this concept hasn't officially appeared yet, so let the students.
Fully discuss why these approximations are formed,
How to get a rough figure? The method of finding the divisor is only mentioned in the textbook.
You can get a rough figure by rounding. What is the rounding method? Most students are not familiar with it.
I realized that many children didn't understand, so I let them understand it literally. What does the "Fourth Hospital" mean? What is the number?
Can you give up? What does "five advances" mean? How many numbers can you enter? Then I wrote a few twos on the blackboard.
Count,
Ask the students to observe and think about whether these numbers should be rewritten as "four" or "five".
Because students have
The manager understands the meaning of "rounding".
They quickly said:
In high spirits.
Under my guidance,
Through observation,
Analyze, discuss and judge how to get the approximation of two digits by rounding. Students' thirst for knowledge
Desire is aroused,
On this basis, we will study how to find the approximation of multiple digits. Find out which one to fuck
Rounding is the key to teaching.
I emphasize by asking questions:
(1) Where is the mantissa after "ten thousand" omitted?
Rounding? (2) Where is the mantissa after omitting "100 million"? And ask questions in due course:
get through
What did you find about the above two questions?
Let the students find out which number is followed by the last number omitted.
Figures are rounded)
. The whole teaching process allows students to experience in comparison, by comparing the similarities and differences between data.
At the same point, extract the divisor method. Only through this process can the intuitive experience be mentioned.
L, into the process of learning mathematics.