Topic: How much is left (understanding of subtraction)
(** 1 class hour, 1 class hour)
Teaching purpose:
1. Understand the significance of subtraction in specific situations and activities.
2. Can list and read the subtraction formula, and can correctly calculate the subtraction within 5.
3. Can solve the simple subtraction problem in life according to the provided situation.
Teaching emphases and difficulties:
Understand the meaning of subtraction, correctly calculate the subtraction within 5, and be able to contact
Life actually solves real life problems.
Teaching aid preparation:
Situation map, language card, multimedia
Teaching date: year month day
Teaching process:
Step 1: Create a situation.
Show the fruit tree chart, let the students observe the chart, read the information in the chart, and let the students use their own language.
To describe this information.
2. The significance of experiential subtraction
1. Guide the students to observe the pictures and say what they see with a smile/
2. According to the diagram, ask questions and lead to subtraction.
There are five apples on the tree, but two are missing. How many apples are left on the tree?
How do you know it's three? As can be seen from the figure. Less than five. Two equals three.
Two fifths can be expressed by a subtraction formula, and the middle is 5-2 = 3.
The symbol is a minus sign, and the formula reads 5 minus 2 equals 3. It means there are five apples, and two have been removed.
There are three left.
Put a pendulum with a disc instead of a fruit. First, put five disks to illustrate its meaning.
What do you mean by taking two more, and what do you mean by the last three?
Change the formula 5-4 = 1 and swing it.
4. How many cookies are left? Say and count.
Guide the students to say how many pieces were there, how many pieces were removed and how many pieces are left?
Start swinging, draw a picture and list the formulas.
5-2 = 3 What do these numbers mean?
Can you name a few subtraction formulas like this and read them out?
6. Find the subtraction problem around you
Children can subtract, can you find the subtraction problem around them?
Three. Consolidation exercise
1. Drawing calculation book P27.
Students cross out the circle first, then list and say what they think.
have a try
Talk to each other in the group first and see how many to move. what to use
Method calculation, and then formula calculation.
3. Look at the formula and say it.
Exhibit 4- 1 = 3 Organize students to carry out group activities. For example, this formula can be expressed as follows
What?
Four. Expansion and extension
Complete exercise question 2.
The last two open-ended questions require that the chart should correspond to the formula.
Ask more students with different answers to express their thoughts. Why is this listed?
Verb (abbreviation of verb) course summary
Review this lesson and talk about your feelings and gains.
Blackboard design:
How much is left
Understanding of subtraction
There used to be five apples on the tree, but two were dropped. How much is left?
5-2 = 3 is pronounced as 5 minus 2 equals 3.
Work design:
After practicing 3 to 6.