During the National Day holiday, my mother and I went shopping in the supermarket, looking for kilograms and grams. When we walked into the supermarket, we first came to the biscuit cabinet. Among so many dazzling cookies, I chose my favorite casual cookie. I looked at it carefully and finally found the "net content100g" in the corner, indicating that the weight of this packet of biscuits excluding the bag is100g. If there is100g,
Then we went to the place where we bought rice. I found that a bag of rice costs 10 kg. If our family eats 2 kilograms a day, our family will eat 60 kilograms a month, which is six bags of rice.
Later, I saw 16 eggs, about 1 kg, a pineapple about 2 kg and a watermelon about 3 kg.
Today, I have gained a lot. I feel the knowledge of kilograms and grams in mathematics. Mathematics is really important in life.
2.& lt A Little Mathematical Misunderstanding
Many people think that Arabic numerals were invented by Arabs, but I have always been skeptical about him. As I expected, the teacher introduced the real origin of Arabic numerals in math class today. It turned out to be a misunderstanding! The real inventors of Arabic numerals were Indians, because the navigation industry of Arabs was very developed at that time, and they spread the numerals from India to Arabia. Europeans learned this simple counting method from their books and thought it was invented by them, so they called it Arabic numerals. Later, this misunderstanding spread to China.
Finally, I really want to say to the Indians, "Thank you for bringing us so much convenience. Because of this, I like math very much. The digital kingdom is not only magical, but also rich in historical knowledge of mathematics.
5. < Discovery > III (4) He Chao
Today, I found a math problem at home.
I found that a cup of cola is 800g, a cup of green tea is 500g, and a cup of iced black tea is unknown, so I added a message-iced black tea is 200g less than cola, so how many grams do you need for three cups? So, I calculated according to the teacher's method: 800-200=600, then 600+500= 1 100, and finally1100+800 = 1900, so it is.
I think there are many math problems in daily life. I hope children can observe more math problems around them.
6.& lt ingenious addition and subtraction;
Addition and subtraction are indispensable in our life. There are many things around us that need to be added and subtracted. For example, in school, we calculate scores and numbers-in life, my mother goes shopping to pay for food; At home, addition and subtraction are also used to calculate monthly expenses. All this is related to addition and subtraction, so addition and subtraction play a very important role in our life.
Addition and subtraction are wonderful!
7.& lt On the way to Tianmu Lake
Now, our math class is solving the practical problem of two-step calculation.
Today is Sunday, and my family went to Tianmu Lake to play. On the way to Tianmu Lake, I thought of such a problem.
When the bus approached the first stop, I saw eight people get on the bus and three people got on the second stop. If the number of people getting on the bus at the third stop is twice that at the first and second stops, what is the number of people getting on the bus at the third stop?
Children, will you solve this problem? Try it with what we have learned.
8.& lt24 Hour Timing Method;
24-hour timing is really omnipotent. If you don't believe me, let's see how I spend the weekend: first, get up at 7:30, then wash my face at 7: 45-8: 00, have breakfast at 8: 00-8: 15, and have breakfast at 8: 15-9: 655. Lunch time is10: 30-11:00; Lunch time is11:00-15: 00; Lunch time is 15: 00-65438. 17: 30- 18: 00 for dinner, 18: 00-20: 00 for TV, 20: 00-2100 for computer, and 2100 for sleep. If you have such an idea, you must also write a diary like this!
9. Many a mickle makes a mickle
This afternoon, my mother and I went shopping in the supermarket.
When we finished buying what we needed, we were about to leave. I saw sausages on the shelf, so I asked my mother to buy some sausages, and my mother agreed. But just a few steps later, I saw a package with the same brand and weight on the shelf, which contained 10 pieces at 4.30 yuan each. Do you want to buy a pack or a slice? I hesitated. Suddenly, my mind turned and I understood. Just compare which one is cost-effective. So I started to calculate: if I buy 65,438+00 retail goods, each price is 40 cents, which is equal to 4 yuan, and the whole package price is 4.30 yuan, 3 cents more, so I decided to buy bulk goods. I told my mother the process of my calculation, and my mother praised me for my love of thinking.
Mathematics news
Today, we sent out the math newspaper for primary school students. This issue is really wonderful.
It talked about how to keep books with you, how Mao Yisheng developed his memory and the origin of Arabic numerals. On the one hand, there are many math skills, such as how to find the rules and how to remember knowledge, and on the other hand, there are some math stories, from which I have gained a lot of content that I can't learn in class.
Therefore, I think I can master more knowledge every time I read the math newspaper, and I like it very much.
"The Mystery of Mathematics" Zhang Na Hutangqiao Central Primary School
Mathematics is everywhere in our life. For example, how much does it cost to buy food in the vegetable market? How much does it cost to buy things in the supermarket? ..... Besides, knowing kilograms and grams, you can calculate the price of the weighed things yourself. So, is mathematics important?
So, I want to remind you-you must learn math well!
Mathematics is mysterious, it can let us know some unknowns. So some children think math is a bit difficult, and sometimes they have to ask a tutor.
But math is also very flexible. Besides what I just mentioned, there are many kinds of mathematics in life!
Baby Tintin recited the formula.
On Sunday, Baby Tintin recited the formula, but when he recited it until March 8th, he stopped.
At this time, it happened that my sister came over, and Tintin hurriedly asked, "Excuse me, March 8?" ……"
My sister said angrily, "You are only 38 years old! Learn to swear before you get old! "
My mother, who was cooking in the kitchen, heard the voice and answered, "March 8 Women's Day".
I snickered at the side, but in fact they all misunderstood: Tintin didn't swear or remember festivals, but recited the formula:)
Ha ha laugh .....
Compare, who uses more units? 》
In the morning, I got up from the bed about 2 meters long;
Pick up a toothbrush about 6 cm long and start brushing your teeth;
Then, I picked up a towel 40 cm long and 20 cm wide and began to wash my face.
After washing, I took a bowl weighing about100g and filled it with porridge.
After eating, I came to school with a schoolbag weighing about 2 kilograms on my back and started a 40-minute morning reading class.
After two classes, we all stood under the flagpole about 7 meters high to do exercises.
Well, that's all I have to say. Can you speak more fluently than me?
weigh
Today is Saturday 10, 15. My father and I went shopping in South Street.
At 8 o'clock in the morning, we arrived at South Street by bus. It happened that there was an old man by the platform, and there was a talking scale beside him.
Seeing me coming, grandpa smiled and said, "Little friend, do you weigh yourself?" ?
I asked a little curiously, "How much does it cost to weigh it once?"
Grandpa replied cheerfully: "You can only weigh 1 yuan at a time, and you can also measure your birth height!"
I thought to myself: this is really killing two birds with one stone!
So I stood firm on the weighing scale. Grandpa turned on the switch and only felt something soft touch my head. Subsequently, a small rectangular piece of paper was printed on the machine, which read: "Weight: 27.0 kg, height 132.5 cm"! In the past six months, I have grown 4 centimeters, but what about my weight?
At this time, I remembered that the teacher said that "kilogram" had another name "kilogram" in math class. I didn't expect to meet you today, and I know that I have gained 2 kilograms!
I was so happy on the way back! I must exercise my body!
Interesting math problem
Today, I saw a very interesting topic in the book, and now I will introduce it to children.
Xiao Zhao, Ding Xiao and Xiao Zhang are teachers, doctors and lawyers respectively. They only know: (1) Xiao Zhao is older than the teacher; (2) Xiao Zhang and the teacher are of different ages; Xiao Zhao and a lawyer are friends. Can you infer who are teachers, lawyers and doctors?
According to (1) Xiao Zhao is older than the teacher and (3) Xiao Zhao is a friend of the lawyer, it can be inferred that Xiao Zhao is neither a teacher nor a lawyer, so Xiao Zhao is a doctor. According to ②, Xiao Zhang is a lawyer and teacher, Xiao Zhao is a doctor, so the rest of Ding Xiao are teachers.
This topic is very simple. I used the elimination method. For example, according to conditions (1) and (3), it can be seen that Xiao Zhao is neither a teacher nor a lawyer. The answer can be obtained by analogy. In the process of learning mathematics, as long as we master the methods, we can solve all the problems, but we can never expect to have fun from mathematics.
Numbers in motion
165438+1On October 24th, our school ushered in the annual sports meeting.
There are 24-meter running, 60-meter running, 100-meter running, 200-meter running, 400-meter running, 800-meter running, 1200-meter running, 1500-meter running, 2000-meter running, as well as softball and long jump. I found that they are all calculated in terms of time and length, and winning or losing is determined by numbers.
Exercise is also inseparable from mathematics!
& lt The Harvest of Reading Books "
Today, I read a book, The Story of Science, and I feel very heavy.
It tells the story of a mathematician. His family is poor, but he is eager to study, so he sends him to school. But he's not serious. Keep playing. One day, the teacher talked to him: "the food you eat and the money you spend on school are the fruits of your father's hard work." Who do you deserve if you don't study hard now? " He was inspired a lot. He thought: When I grow up, I want to be an astronomer and a writer.
But later, influenced by a teacher who came back from studying in Japan, he turned his interest to mathematics. Do you know who he is?
He is Sue, a famous mathematician in China.
Smoking is harmful to health. Dad smokes a newspaper every day, 20 cigarettes per pack. I learned that each cigarette can shorten people's life span by 3 minutes, so it will be shortened every day.
20X3=60 minutes = 1 hour life, which shortens life by 365 days per year X 1 hour =365 hours. So I said to my father, "Smoking is harmful to health."
self-introduction
Hi! Hello everyone! My name is rectangle. My body is very long. I have four sides and four right angles.
Hello! Hello everyone! My name is square, my body is square, I have four sides, but my four sides are the same, I have four right angles.
We have a lot in common: we all have four sides, the opposite sides are equal, and we all have four right angles; The difference in length is that each side of a square is equal.
Look, how beautiful we are!
Rectangular and square
There are many rectangles and squares in life.
The surface of the table is square, so is the surface of my bed, and so is the surface of the clock. ...
Let's talk about rectangles. The front of the book is rectangular, the front of the door is rectangular and the front of the chair is rectangular. ...
You see, rectangles and squares are so common in our lives. If you look around like me, you will find a lot of interesting math knowledge. If you don't believe me, try.
The role of perimeter
There are many rectangles and squares in life, and they all have perimeters. What's the use of perimeter?
I found that it has great skills in our life. For example, if we want to build a fence for a rectangular flower bed, if we don't know the perimeter, the workers need to surround it, and so on. If it is too short, it must be lengthened, if it is too long, it must be repeated. Look at what a waste! So just know the circumference and measure it once, which saves time and wood. How convenient!
If you are interested in circumference, you can also find it in your life, record it and share it with other children!
Various graphics
There are all kinds of figures in our world, such as triangle, square, rectangle, circle, trapezoid and so on.
In daily life, some figures have different characteristics, for example, the four sides of a square are equal and the four corners are right angles. There are many square objects in life, such as the surface of TV, the surface of windows and the surface of cabinets, and there are many kinds of triangles, among which the right triangle is a pair of triangular rulers. I found a triangle with equal sides. Another triangle, one side is half of the other side, and one angle is also a right angle. In daily necessities, I find that there are fewer triangular things than square and rectangular ones. At home, I only found triangular air conditioning racks and flower racks.
Can you make these different shapes into any interesting shapes? Give it a try and you'll find it interesting.
Our research.
Our study is rectangular, 7 meters long and 4 meters wide, facing north.
As soon as I entered the door, I faced a big purple desk, which was also rectangular, about 2.5 meters long and 1.2 meters wide. That's my father's desk, and there is a smaller rectangular desk next to it, about 2 meters long and about 1 meter wide. My mother often reads books here.
In addition, there is a row of sofas and a coffee table against the wall, and there is an air conditioner, a water dispenser and a bookcase in the corner, which are also rectangular.
Finally, I found that I didn't see a square in our study. How strange!
This is my study. Welcome children to my home to play!