"Let Who Eat Well First" is a humorous and vivid picture book story with an unexpected ending, which perfectly contains boring "ranking" in a wonderful story and perfectly combines picture books with mathematical knowledge and life experience. So I designed this math activity according to the actual situation of children. In the activity design, I take the story situation of "who should eat first" as the starting point, and use the situation to promote the continuous construction of children's experience in ranking height, body shape and weight, and the activity goals are naturally displayed, diffused and achieved one by one in the process. Let children express, explore and operate in activities, learn mathematics knowledge imperceptibly, and experience the fun brought by sorting. Teaching objectives

1. Know that sorting according to different characteristics of things will have different results, and preliminarily understand the reversibility of sorting.

2. Be able to sort according to requirements and try to record the results.

3. Actively participate in sorting activities and experience the fun of sorting.

Teaching emphases and difficulties

1. Key point: Sort the animals according to their height, mouth size, ear length, tail length and weight, and understand the reverse sort.

2. Difficulties: In the game of counting stones, compare the light and heavy relationship between animals and try to record the operation results with ",=".

Teaching method design

Each child has animal-operable classified materials and weight records, and the teacher assists the teaching with the help of interactive electronic whiteboard.

Selection of teaching media and resources

Picture book story book "Who should eat well first", whiteboard courseware, pictures used in the design process and clicking the corresponding small buttons.

Classroom teaching tools and software

1. Material preparation: activity whiteboard courseware, children have record sheets, pencils, erasers and animal classification pictures.

2. Experience preparation: understand the seesaw and know that the seesaw is flat, which means there are high and low.

Teaching implementation process

First of all, understand the main characteristics of animals and peaches.

1. Understand the main characteristics of animals.

(1) Teacher (click courseware): Today I invited some animal friends to everyone. Look, who is there? Count, how many people are there in a * *? (Monkeys, giraffes, rabbits, rhinos, crocodiles, caterpillars; 6 friends)

(2) Teacher: These animal friends all have an obvious feature. What is this? For example, we can call it a rabbit with long ears, a crocodile with a big mouth, a tall giraffe, a monkey with a long tail, a rhinoceros with a big belly and a caterpillar.

2. Understand the characteristics of peaches.

(1) Teacher: Hey, what are they all looking at? (peach)

(2) Teacher: Look, what does this peach look like?

(3) Teacher: Wow, such a big peach in the shape of love, red and yellow, looks delicious and makes the animals drool. But six animals have 1 peach. Who should eat it first?

Second, combine stories to guide children to classify animals according to a certain feature.

(a) according to the animal's height, size and length.

1. Sort by height.

(1) Teacher: "How about eating in order of height?" The giraffe straightened its neck and said something first. Then you have to measure first to see who is the tallest.

(2) Teacher: So, each of them found a big tree and began to measure their height. (Click on the next page) Please take a closer look. Did someone cheat and foul? (Children tell)

(3) Teacher: Yes, the height should be measured at the same level. Stand up straight, not counting ears and tail. Look, they are standing. Who is the tallest? Who is the second tallest? What about the third highest? Whose turn is it next? The fifth tallest? Who is the shortest? (The teacher writes the ranking figures under the animals.)

(5) Teacher: According to the height, giraffes are the tallest, so eat peaches first.

2. Sort by mouth size.

(1) Teacher: "No, the peach with the biggest mouth must be eaten first." The crocodile spoke with its big mouth open. So, the animals opened their mouths wide. Please have a look and compare. What should I do in the order of mouth size?

(2) Ask individual children to operate the sorting on the whiteboard, and the teacher will use the courseware to verify (click on each animal's mouth, a circle of different colors will appear, which is convenient for dragging and comparing), and sum up the sorting together. The crocodile has the biggest mouth and should eat it first, as he wishes!

3. Sort by ear length.

(1) Teacher: At this time, Lopunny and the long-tailed monkey disagreed. What would they say?

(2) Rabbits: sorted by ear length (sorted by children's operation data)

Monkey: Sort by tail length.

Ask the children to arrange the tail length according to the idea of the long-tailed monkey (the tail mark appears in the stars)! (The children said that the teacher dragged the animals to classify)

Comment, the teacher and the child sum up the length of the tail together.

If you sort by ear length (there are ear marks on the dotted flowers), how should you arrange them? Explain the operation requirements: the teacher has a sorting table here, and the red flag is the starting point. Please arrange the animals neatly on the black line in the order of ear length. (children's operation)

Comment, the teacher and the child sum up the length of the ear together.

Third, guide children to record and sort according to the weight of animals.

1. Discuss the specific gravity method.

(1) Teacher: The big-bellied rhino stamped his foot and said, "No". What will it require? You really talked about its psychology, that is, in order of weight.

(2) Teacher: How should I weigh it? What's the best way? (Pointing out the seesaw) Weigh with the seesaw, with small animals at one end and stones at the other.

Teacher: Think about it. What do you mean the seesaw is flat? The same weight can be represented by the symbol "=". Is it heavy or light to walk? What about low hanging? If the left side of the seesaw is heavier than the right side, you can use ">" to record that the left side is lighter than the right side. (The courseware points out one by one, and the corresponding records help children understand)

2. (Click on the first star, and a "weight record" will appear.) The teacher explains the operation requirements: In order to be fair, please invite our children to be judges. Look at which small animal is weighing first, then count the stones on the seesaw and record them in the box under the "stones". Finally, see if the seesaw is flat or upturned, and record it with corresponding symbols in the middle.

3. Children's records, teachers' observation and guidance.

4. Communicate the operation results, and the teacher records the feedback to correct.

5. Guide the children to look at the record table and sort their weight together.

Teacher: Then let me take a look at this record and rank the weight of small animals! (Click on the second star to display the sorting chart, click on the third star to disappear the animal weighing chart and six animals appear to be dragged) (The child said that the teacher ranked) It seems that the peach should be given to the heaviest rhinoceros first.

Fourth, guide children to think about reverse sorting.

1. (Click the little star icon courseware in the page when summing up)

Teacher: The caterpillar thinks, "Who is the tallest, the giraffe is the first; When the mouth is the biggest, the crocodile comes first; When the ears and tail are the longest, rabbits and monkeys are the first; Who is the heaviest? The rhinoceros was the first. What should it win the first place?

2. Yes, why start with the biggest one! The caterpillar also thought of it. We can do the opposite. No matter who is the youngest, the caterpillar is the first. No matter who has the smallest mouth, the caterpillar is the first; The ears are the shortest, the tail is the shortest and the weight is the lightest. Isn't the first place all caterpillars? Everyone agreed, so the caterpillar happily got into the peach and ate it first.

Fourth, expand and extend.

1. Teacher: Think about it. In our life, is there a situation of "growing up, from short to high, from short to long"? (while waiting in line, sitting in a seat, doing exercises)

Teacher: Children, there are many ways to compare in our life. If you look closely, you will find many arrangements. Animals found the first place according to their own characteristics. In fact, each of you has the first place. Please go back and think about what you are best at.