Time flies and the day is coming to an end. I believe everyone must be deeply touched. It's time to settle down and keep a diary. But how can I keep a diary to shine? The following is the third grade math diary collected by Bian Xiao for reference only. Let's have a look.
Math diary 1
Today, my mother and I went to the bookstore to buy books. I found a puzzle in a book called Interesting Mathematics. The problem is this: Bill spent 10 yuan bought a dog, sold it 15 yuan, then spent 20 yuan to buy it, and finally spent 25 yuan to sell it. Did Bill finally make money or lose money? I feel that I have bought and sold, sold and bought again and again, and my thinking has always been confused. I went to ask my mother, and she said, "If you can classify according to the number of' buying' and' selling', you will be suddenly enlightened. I think: the money used for "buying" is 10+20=30 (yuan). Money earned by "selling": 15+25=40 (yuan). Obviously Bill made money, earning 40-30= 10 yuan.
Ah! What a rich knowledge of mathematics!
Grade 3 math diary 2
Today, my mother took me to the market to buy food. I found a rectangular electric appliance on each booth, which was marked on the front: kilogram gram. I asked my mother curiously. My mother said that the grams and kilograms you just saw are used to weigh things and express weight units. When I got home, I searched a lot of things at home: a box of tea 125g, a lipstick 1g, and a box of urea cream 48g. Then my mother told me that all solids that can be picked up by hand are represented by grams, and liquids that cannot be picked up by hand are represented by L. I don't know much about life.
Math diary, grade three, chapter three.
Today, I learned what is vertical. Originally, two straight lines that intersect at right angles are perpendicular to each other. One of the straight lines is perpendicular to the other, and their intersection is called vertical foot.
In addition, I will draw vertical lines and parallel lines. Draw a vertical line from a point outside the line, and the length of the line segment between this point and the vertical foot is the distance from this point to the line.
Well done! After these two classes, I gained a lot of knowledge.
Math diary, Grade Three, Chapter Four.
There is a height ruler on the wall of our house. I use it to measure my height every year. Last year, my height was 1m 10cm, and this year's height is 1m 16cm,110 = 6 (cm). It has grown by 6cm this year.
I asked my mother, "When can I grow as tall as Yao Ming?" Mom said, "As long as you eat more every day, don't be picky about food and keep exercising, you will grow into a giant like Yao Ming in the future." .
Math diary, grade three, chapter five.
One weekend, my good friends from the yard came to my house to play. I was going to play a trick on her and say, "Let's play a game. Each of us can only shout 1, 2, 3, 4, 4. Whoever calls 32 first wins, I'll count. If you lose, you will be punished. I'll shout first, 2. " She thought for a moment and said, "No ... you already know the law. I'm going to lose anyway."
Because 32-2 = 30, 30 = 5× 6, 5 = 1+4 = 2+3, as long as the sum of the number I shouted with her and the first number is 2, I can win. I wanted to use this rule, but I didn't expect it to be seen through by her.
It seems that I must strengthen my knowledge of mathematics.
Math diary, Grade Three, Six.
Today, my mother asked me to buy four lettuce and two yuan of tofu. When I arrived at the vegetable shop, I chose four lettuce, and then asked my grandmother to bring me two yuan of tofu. Then grandma told me that lettuce tofu is RMB. I worked out how much a * * * is worth. One * * * is Yuan, so she should give me change. I went home smoothly after paying the money.
After returning home, my parents praised the food I bought.
Math diary, grade three, chapter seven.
1 In August, I went to Penglai Long Island with my parents, grandparents and my uncle. We took the New Century bus at 9: 00 p.m. and arrived at Long Island Port at 7: 00 the next day. Some * * * left 10 hours or so.
We went to Long Island by boat for about 40 minutes. We live in a fisherman's yard and eat seafood every day, including shellfish, jiaozi with fish stuffing and fried yellow croaker. In the morning, let's go fishing by boat. One adult ticket for 40 yuan, and one child ticket for 40 yuan Bimigao, but not for 20 yuan.
Neither my brother nor I exceed 100 meters, so our family of three is exactly 100 yuan. There are seven people in my family, 240 yuan. I saw the fisherman's uncle hit a shell and a starfish. Let's go to the seaside night market at night. My mother bought me a jade necklace and a puppy made of three shells. I also bought three jade necklaces for my brother and sister, one of which cost 50 yuan.
Math diary, Grade Three, 8
Today, we went shopping. We bought 2 Jin of cucumber, 1 Jin of tomato and 2 Jin of my favorite potato. On the way back, my father asked me, "There are just four cucumbers. There are three of us. My mother doesn't eat cucumbers. How many do we each eat? " I remembered the division I had learned before, and I said, "4 division; 2=2, everyone eats two. " Dad nodded and smiled and said, "You're right!
I am very happy today. Not only did I go shopping with my father, but I also counted them. That's great.
Math diary, Grade Three, 9
Tonight, I just finished my homework and have nothing to do. I said to my mother, mom, I have finished my homework. What should I do now? Mom said: Now, just buy me 3 Jin of apples! I said yes. Mom gave it to me 10 yuan said, buy another half catty! I readily agreed, happily took the money to the fruit shop, picked three and a half pounds of fruit, and said to the clerk, help me calculate. Aunt said: You can calculate first.
I thought about it and said to my aunt: Is it 3×3=9 (yuan), then put 3 yuan ÷2= 1 yuan 50, and finally put 9 yuan+1 yuan 50 = 10 yuan 50. I said again: no, aunt, I don't have enough money. I still need 50 cents. What should I do? I thought about it and said, then make up my pocket money! I took out my pocket money and put it in. Say to aunt: that's enough now. Aunt said: you are so smart. You used your wisdom to buy apples!
Math diary 10 in the third grade.
I have been thinking about another method to calculate the volume of a cylinder these days. Based on my feelings, I have listed such an equation: diameter× diameter× height× 4.
After coming home from school, I began to prove whether this formula was correct. I tried. The solution in the textbook is exactly the same as my solution for calculating the volume of a cylinder. I have tried many times, and the result is the same.
I feel very distressed. What do I mean by this solution? After some thinking and proof, I found that a cylinder is regarded as a cube with equal diameter and height. Then calculate the volume of the cube, and then according to the ratio of the cylinder to the cube is: 4, it becomes the volume of the cylinder.
Math diary 1 1
Today, grandma bought a duck weighing two kilograms, which cost 15 yuan per kilogram. She also bought two potatoes and half a catty of pork. Vegetables cost two yuan a catty. Grandma bought a catty and a half and used 3 yuan.
In the evening, grandma cooked potatoes, fried vegetables and stewed ducks. Divide the potatoes into five parts. My mother and I ate two-fifths and my grandmother, aunt and sister ate three-fifths. Grandma also boiled the soup and divided it into six parts. We drank four-sixths of the soup, and this score can be divided into about two-thirds. This score is also the simplest score. Mom told me to eat more soup dregs, because 15% of the nutrition is in the soup and 85% is in the soup dregs.
Today, I not only know math knowledge, but also know that nutrition drugs are well matched.
Math diary 12 in Grade 3.
A few days ago in math class, the teacher gave us an application problem, saying that the largest bird egg in the world is ostrich egg, and its egg has 1300 grams. How much does the smallest egg weigh? I put a question mark in my mind.
After surfing the Internet and reading books in various ways, I finally found the answer in the China Youth Encyclopedia: the smallest egg is a hummingbird's egg, and the hummingbird mother lays 2~ 1 egg at a time, which is only the size of a bean, and each egg weighs grams. About 200 hummingbird eggs are as big as eggs. Hummingbirds can fly out of the nest for food after living for about 20 days and start an independent wild life.
What interesting knowledge, it can not only learn, but also increase extracurricular knowledge. It really kills two birds with one stone.
Math diary 13 in the third grade.
In the evening, my brother said he was hungry and wanted to drink milk powder. Seeing my mother washing clothes, I helped my brother make milk powder. But I didn't know how much water and milk powder I needed, so I ran to ask my mother. My mother told me that I need 180ml of' warm water'. I asked my mother how many spoonfuls of milk powder she needed. My mother said, "How many spoonfuls of milk powder do you need for 30 ml of warm water, 1 80 ml of warm water? Calculate it! " When I added it, I counted 30: 30+30 = 60, 60+30 = 90, 90+30 = 120, 120+30 = 150,150+30. Finally, the sixth 30 adds up to 180. I quickly told my mother that it was six spoonfuls. Mom smiled and said, "That's right, but if you learn multiplication and division, it will be easier to calculate.". 180÷30=6, which can be calculated soon. " It can be that simple!
Mathematics is around us, I want to study it well!
Math diary 14 in Grade Three.
It was sunny this morning, and I went to hangzhou paradise to play with Xia Er's sister.
We went to play the Ferris wheel. Ferris wheel has four carriages: red, yellow, blue and green. Each color has four compartments, and each compartment can accommodate four people. My mother asked me, "How many people can sit in all the yellow cars?" How many people can sit on the whole Ferris wheel? "I quickly replied:" Yellow can seat 16 people, because yellow has four cubicles, and each cubicle can seat 4 people, so it is 4+4+4 = 16 (people). Ferris wheel has four colors, each color is the same, so it is16+16+16+16 = 64 (person). The ferris wheel can seat 64 people. "After answering the question, we got on the Ferris wheel together. Dad also ordered us something delicious. It was really delicious and fun.
After we got off the Ferris wheel, my father told us, "This will be easier when we learn multiplication." I am looking forward to learning multiplication!
Math diary 15 in Grade 3.
On Lunar New Year's Eve, my parents took me to Taicang? Wanshan Park is a paradise.
I first went to the ticket booth and bought a ticket for "Luxury Flying Chair". 10 yuan. There are many swing seats around a big pillar. At the beginning of the turn, the outer layer of the big cylinder rises slowly, and the seat rises continuously when turning, and people fly around in the seat. When they flew faster, some people began to scream. But I'm not scared at all. Then we bought three tickets for "Basket sightseeing bus", one for 20 yuan and one for 60 yuan. Finally, my mother and I went to do a "spacewalk", each time 15 yuan, which is 30 yuan. In this case, we spent a total of 10+60+30= 100 yuan.
In the process of playing, I got to know my classmates. He has a package ticket for 40 yuan in his hand. I heard that he can always play eight projects. It suddenly dawned on me that if we had bought the 40 yuan package, it would have cost 100 yuan to play these three games without buying the package, but we only used the 40 yuan package, which was much cheaper than 60 yuan. Alas, what a loss! So I want to tell the children that if you want to save some money when you go here next time, buy a package ticket. This is my suggestion!
Math diary 16 in the third grade.
Today, my family went to the supermarket to buy things. We first went to the kitchen supplies counter and bought two fresh-keeping bags, one RMB * * *. My mother asked me 1 how much it costs? I can't help saying, "1 cylinder is yuan." Then we went to the commodity counter, and we bought three large shoe polishes, one *** 15 yuan. Dad asked me how much is one? I said, "15 yuan divided by 3 equals 5 yuan." Then we went to the toilet paper counter. We bought three packs of toilet paper, 18 yuan. My brother asked me, "1 How much is the toilet paper?" I said confidently, "Six dollars." Then we went to the apple counter and bought 3 Jin of apples, each Jin of 4 yuan. My uncle asked me, "How much is a * * *?" I said without hesitation, "Yes 12 yuan." We finally came to the dental counter and bought two Yunnan Baiyao toothpaste and one from 28 yuan. My mother asked me, "How much are two?" I hesitated and said, "56 yuan."
It turns out that shopping also has math!
Math diary 17 in Grade Three.
In today's interesting math class, xu teacher taught us to make three-dimensional figures with plasticine and toothpicks. Xu teacher asked us to build a prism and a cube according to the three-dimensional figure on the big screen, and then create an interesting three-dimensional figure by xu teacher's method. The children used their rich imagination to come up with all kinds of three-dimensional graphics. Some built cuboids to be done in the next class, some built the same shape as houses, and some built a very complicated iron tower, especially Li Yuxin, who had a great effort to build a three-story house. It was not finished until class was over, and her work was praised by the whole class. This interesting math class makes students understand that they can also build complex graphics with the simplest materials and make them ever-changing.
Today's math class is really interesting, and the students are smiling! I hope there will be more and more such classes in the future, which will make our math learning more and more enjoyable!
Math diary 18 in Grade Three.
I learned modern intelligent puzzles in the summer vacation. Tangram1* * has 5 pairs, each pair consists of 7 pieces. Mom asked me how much this * * *? Here's my calculation. Add 7+7+7+7=35 in my notebook. Mom told me that I can work it out quickly with the multiplication formula I just learned! I had a brainwave and silently thought about the multiplication formula related to 7. "Five-seven-thirty-five" is the same as my answer. Wow! The original multiplication formula is so convenient. Mom gave me a thumbs-up sign.
Tangram can be spelled in pairs or in pairs, and can be spelled into people, fish, Chinese characters, rockets, boats, animals and so on. As long as you are willing to use your head, you can spell out all kinds of figures. Today, I spelled one by one until I got nine pairs. What I like best is the picture of mother and daughter having fun together. Look! I used a long right-angle board and a big board to spell out my mother's body, just like being held in my arms and laughing together.
Modern puzzles are really interesting. Let's play together!
Math diary 19 in Grade Three.
Today, my good friend Zhou naturally went to read a book. We came to the reading room. There are so many books in the reading room! There are picture books and story books. We first came to the favorite picture book area. I counted with Zhou Ziran and found that there were 20 books in each line.
At this time, Zhou naturally wanted to test me and said to me, "Do you know how many books there are in the picture book area?" I looked up and counted, and found a * * * with three lines and 20 copies each. Then the picture book area has 20+20+20=60 (this). Zhou Ziran agreed with me after listening to my answer.
So, we read together in the reading room from 1 pm to 2: 30. I read 30 pages of picture books and 28 pages of story books. I read 30+28=58 (pages) for one and a half hours. One hour equals 60 minutes, and half an hour equals 30 minutes, which means I watched 60+30=90 (minutes).
How time flies when reading! Today is really a happy day!
Math diary, Grade Three, Chapter 20.
Today, I play dominoes at home.
Domino has four colors: light green, dark green, orange and yellow. I counted, there are 20 dominoes in each color. I use multiplication to calculate that the total * * * is 4×20=80 (pieces). I put the dominoes in the domino train and counted them. I can put 27 dominoes at a time. Every small train will automatically arrange the dominoes in a straight line. I thought: How many times does the small train have to run to finish? So I calculated by addition, 27+27+26=80 (one), and the small train has to go three times to complete. The last small train is less than the first two 1 domino. I knocked three ribs at the same time and found that the group with 26 dominoes won. I thought three groups won at the same time, so I took two, so the total became 26+26+26=78 (one). Then, I knocked down three rows at the same time, and this time three groups won at the same time.
Dominoes are really interesting. I'll play new tricks next time!
Math diary 2 1
Happy Saturday came, and my father and I went to work in the shop.
As soon as I arrived at the store, my father got a call from a customer. I wanted to buy a batch of plates and put them on the insulation table. Dad answered the phone and said to me, "Dad tested you today!" " ! The customer wants to buy 4 sets of pots on the heat preservation table. 1 There are 6 sets of pots on the heat preservation table. A * * *, how much do you want? "I think in my mind, 6+6+6 = 24 (a). Dad asked again, "Do you have any other convenient and quick algorithms? "On second thought, I just learned the multiplication formula" 4624 "in the summer vacation, and I soon figured it out, which is the same as the answer to addition. Dad gave me a thumbs-up when he heard the answer. Dad said, "The number of pots in our warehouse is 12. How many boxes do we need to send? " I quickly meditated in my mind that 24- 12- 12 = 0 is exactly two boxes. I quickly said to my father, "Two boxes will do. "Dad smiled happily and invited me to eat ice cream.
It turns out that mathematics is everywhere in our lives.
Math diary, Grade Three, Chapter 22
Tonight, after finishing my homework, my mother asked me to review the multiplication and division formula. Thinking of the formula, I sighed, reluctantly sat at my desk and began to work on it one by one. Two times two makes four. At this moment, my father heard my weak voice and came over. He looked at me seriously and suddenly smiled. He told me that mathematics is a science and a profound and interesting knowledge. Many inventions in our lives are inseparable from mathematics.
At this time, my father looked at the multiplication table and told me a very interesting multiplication formula with his fingers. He asked me to stretch out ten fingers and then stretch out one in turn. In this process, the closed hand index represents another factor besides 9. If you subtract 1, you will get ten digits. The hand index without closing is a single digit. For example, four fingers are closed and six fingers are not closed; Then, it is four times; 9=36, where 3 is derived from 4- 1 Remember when testing, 4+6= 10, which means ten fingers, haha! Math is really interesting!
Math diary, Grade Three, Chapter 23
Life is full of mathematics, and mathematics is also widely used in life. One afternoon, I met a math problem in my life.
That day, my mother gave me a math problem and asked me to measure the volume of a chopstick and record it in the form of a diary. I sat on the sofa and studied chopsticks carefully. This chopstick is an irregular three-dimensional figure. How to calculate thick or thin?
Suddenly, an idea came to me. Put chopsticks in a container full of water. Isn't the volume of water coming out as big as chopsticks? But chopsticks are too light and will float on the water. So, I decided to wrap the chopsticks with tape and put them in the water. The overflow water minus the weight of the adhesive tape is the size of chopsticks. I follow this method, and the result is that a chopstick is gram.
Through this experiment, I realized that the method is very important, but it may not be successful. Sometimes it is necessary to change the method to succeed.
Math diary, Grade Three, Chapter 24
One morning, the sun was shining and there were no clouds in Wan Li. I was walking in the street after buying breakfast when I suddenly saw many people around a table. I ran over and saw that it was a lottery, and I felt bored when I saw it. I wanted to leave in a hurry, but I suddenly became interested when I heard someone say that 50 yuan won the grand prize. Ask the shopkeeper what the rules of the game are. The shopkeeper said, "Here are 24 cards, 12 is 5, and 12 is 10. Grab the 12 card once. If the total number is 60, you can win the 50 yuan Prize. "
I quickly took out 5 yuan and started to touch the cards, but 12 times didn't win the prize. When I got home, I thought it over. The total number is 60, so the cards of 12 must all be 5, and the best case is that they are 5 every time. The first 12 capture 12 5 will cost 6 yuan money, but in case the number of cards captured is 10 or the total number is the same, it means how much money will be spent.
I understood the mystery below and ran to the original store. The manager was gone, and I couldn't find him anymore.