"Grams and Kilograms" PPT

Description

"Grams and Kilograms" PPT

Part One: Introduction to the topic

Classmates, look what they bought in the supermarket? How heavy are they?

The weight of daily necessities.

The weight of an item is measured using a scale.

Weighing in daily life.

Gram and kilogram PPT, part 2 content: new teaching knowledge

Lighter items are measured in grams, and heavier items are measured in kilograms. Weight is measured using a scale.

Key points of knowledge

1. Students can feel and understand the mass units grams and kilograms in specific life situations, initially establish the mass concepts of 1 gram and 1 kilogram, and know that 1 kilogram = 1000 grams.

2. Feel the role of grams and kilograms in life, feel that mathematics is around you, develop a sense of intimacy with mathematics, and cultivate students' awareness of estimating the mass of objects.

Gram and kilogram PPT, the third part: knowledge sorting

Knowledge point 1: Understand the mass units grams and kilograms, initially establish the concepts of 1 gram and 1 kilogram, know the ratio between grams and kilograms and the method of weighing objects with scales, and be able to use grams and kilograms to describe some items in life the quality of.

[Example] Fill in the appropriate mass units in the brackets.

(1) A table tennis ball weighs approximately 3 ( ).

(2) Lei Lei’s weight is 35 ( ).

(3) A puppy weighs 15 ( ).

(4) A pear weighs 110 ( ).

[Analysis] Students in this question tend to confuse length units and mass units. Students need to establish a correct concept of mass units. For weight-related questions, mass units should be filled in. When answering, we should also emphasize that students should see the numbers clearly, think about them in connection with reality, and do not write out the units casually. For example, the mass of a table tennis ball is very light, weighing about 3 grams, not 3 kilograms, and Lei Lei is a person, and his weight should be much heavier, so it is 35 kilograms; the weight of a puppy should be 15 kilograms, not 15 grams. ;A pear is very small, so its mass should be 110 grams.

[Method summary] It is impossible for us to know the mass of every object, so we need to learn to compare it with the mass of objects we know. For example, when filling in question 2, we need to compare it with our own weight.

Knowledge point 2: Use grams and kilograms to solve practical problems. It can help students understand the quality of more common items, establish the connection between mathematics and life, and accumulate life experience.

【Example】Ingenious calculation.

① One watermelon + one pineapple = 8 kilograms One watermelon = ( ) kilograms

② One watermelon + one bunch of bananas = 9 kilograms One pineapple = ( ) kilograms

③One pineapple + one bunch of bananas = 7 kilograms One bunch of bananas = ( ) kilograms

method one:

Because ① + ② = two watermelons + (one pineapple + a bunch of bananas) = ​​17 kilograms, substituting ③ = 7 kilograms into this formula, we can get two watermelons = 17-7 = 10 (kilograms).

So one watermelon = 10÷2=5 (kilograms).

According to ①, it can be concluded that a pineapple = 8-5 = 3 (kilograms).

According to ②, it can be concluded that a bunch of bananas = 9-5 = 4 (kilograms).

Method Two:

Because ① + ② + ③ = two watermelons + two pineapples + two bunches of bananas = 8 + 9 + 7 = 24 (kilograms), it can be concluded that ④ one watermelon + one pineapple + one bunch of bananas = 12 kilograms.

So ④-①=a bunch of bananas=12-8=4 (kilograms).

④-②=One pineapple=12-9=3 (kg).

④-③=One watermelon=12-7=5 (kg).

[Method Summary] This type of question is a question of equal quantity substitution in mathematical knowledge, which enables students to realize the transitivity of the equality relationship, penetrates the idea of ​​equations, and can be mastered by students who have the ability to learn.

Gram and kilogram PPT, part 4 content: Classroom exercises

1. The mother kangaroo just gave birth to a little kangaroo. This little kangaroo is very small and looks only as big as a finger. I heard from my mother that the mass of a peanut is about 1 gram. This newborn kangaroo weighs about 5 peanuts. So how much does this kangaroo weigh?

[Reference answer] A peanut only weighs 1 gram, which is very small and light! The weight of a newborn kangaroo is only as heavy as 5 peanuts. It is so small!

1. Think:

(1) Do you know how much 1 gram weighs? Weigh it with your hands. How do you feel? Please give an example.

(2) How many grains of soybeans are there in 1 gram? And weigh it with your hands.

(3) Do you know how much 1 kilogram weighs? What is the relationship between grams and kilograms?

(4) Do you know which items in life are measured in kilograms? Please give an example.

(5) Do you know which scales use “kilogram” as the unit?

Organize your own language and try to speak.

Gram and kilogram PPT, Part 5: After-class exercises

1. Fill in the brackets with "grams" or "kilograms."

(1) A basketball weighs 400 ( ).

(2) A fish weighs 500 ( ).

(3) A watermelon weighs 5 ( ).

(4) A bunch of bananas weighs 500 ( ).

(5) A carton of eggs weighs 13 ( ).

(6) Dad’s weight is 65 ( ).

2. Choose the right quality and connect them with wires.

3. Fill in ○ with “＞”, “＜” or “=".

4kg○3990g 300g○3kg 2kg○3g

6kg○6800g 9030g○9kg 1kg○1000g

Keywords: Free download of PPT courseware for mathematics in the second volume of the second grade of the People's Education Press, download of grams and kilograms PPT, .PPT format;

For more information about the "Grams and Kilograms" PPT courseware, please click on the Grams and Kilograms PPT tab.

"Problem Solving" Gram and Kilogram PPT:

"Solving Problems" Grams and Kilograms PPT Part One Content: Learning Objectives 1. Further establish the mass concept of grams and kilograms, become familiar with the application of mass units grams and kilograms in life, and be able to use mass units grams and kilograms to express the mass of objects. 2. Introduced by life situations,...

"Grams and Kilograms" PPT download:

"Grams and Kilograms" PPT Download Part One: Learning Objectives 1. In specific life situations, understand the mass units grams and kilograms, and know that 1 kilogram = 1000 grams. 2. Through activities such as weighing, estimating, and weighing, initially establish the concept of mass of 1 gram and 1 kilogram,...

"Understanding Grams and Kilograms" Kilograms and Grams PPT courseware:

"Understanding Grams and Kilograms" Kilograms and Grams PPT Courseware Tell me about which items in life have a mass of approximately 1 kilogram? How many mathematics books have a mass of approximately 1 kilogram? Items weighing approximately 1 kilogram include: 5 math books, 5 potatoes, three cans of beer, 15 eggs...

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Update Time: 2024-06-29

This template belongs to Mathematics courseware People's Education Press Second Grade Mathematics Volume 2 industry PPT template

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