Math diary, Grade Two 1
65438+ 10 month 10 Wednesday sunny
This afternoon, my mother and I played blackjack with playing cards, that is, we showed four playing cards. Whoever works out the score first will win, and we have a good time. There are many algorithms, and some have only one algorithm. For example:? 3、7、8、9,? Its algorithm is: 3? (9-8+7)。 Also: 6,7, 1 9, and its algorithm is: (9-6)? (7+ 1)。 There are some things that we can't figure out at 24: 1 1, 9,13,7; 8, 9, 10, 1 1, we racked our brains and couldn't figure out a way. Maybe this is the secret of mathematics!
This game is full of fun and mystery!
Sophomore math diary 2
65438+ 10 month 10 Wednesday sunny
After supper in the morning, I began to do my homework. I will recite the multiplication formula first, and then write an A book. After I finished writing, my mother gave me several math problems, one of which asked: one math book costs 50 cents, how much does it cost to buy four? I thought about it and said, I need 2 yuan money. Mom asked me how to calculate. I said multiply by 4X5=20 angle, and 20 angle is 2 yuan. My mother praised me happily. I like math better.
Math diary 3, Grade 2
65438+ 10 month 10 Wednesday sunny
165438+1On October 24th, our school ushered in the annual sports meeting.
Track and field has 24m running back and forth, 60m,100m, 200m, 400m, 800m,1200m,1500m, 2000m, 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!
Second grade math diary 4
During recess, in our class. Little doctor? Xiaowen said to his classmates:? Today, I give you an interesting math problem. The topic is: two mothers and two daughters are walking by the river. At least some of them say:? This is not simple! Of course, there are two mothers and two daughters, so there should be 2+2 = 4 (people). ?
Xiaowen shook his head and said, no, whose answer is different? It suddenly occurred to me that my father had told me a similar topic and asked two fathers's two grandfathers. I said, Let's look at the relationship between Xiao Lin and her mother first. Xiao Lin is her mother's daughter, so there are 1 daughter and 1 mother here. Mom is grandma's daughter, so there are 1 daughter and 1 mother here.
On the other hand, two mothers and two daughters are together, and there are at least three people. ? Everyone said:? You really use your mind. ?
mathematics
Grade 2 math diary 5
This morning, the teacher gave out the math exercise books. Let me have a look. What's wrong with an application problem? I said in surprise. A closer look reveals that one step of conversion is missing. I thought it over. How many kilometers should 20400 meters be equal to? 20400? 1000=20.4 (km) Oh, it turned out to be 20.4 km, so I filled it in and gave it to the teacher for approval. The teacher looked at it and said, 340? The unit of 60 should be meters, not kilometers. ? I looked at it, and it turned out that the units in the above formula were wrong. I changed it again, which was approved by the teacher.
Today is the first time I have approved it for the teacher twice. I used to be able to approve it once. I think we can give teachers a batch of good students at a time, so I used to be an upper-middle class in Shi Yang.
Second grade math diary 6
I often get 100 in math exams. Other students asked me if I had any tricks, and I told them that I had one. Correct the wrong book? This helps me a lot.
In the past, when handing out exercise books or test papers, I only looked at the grades or scores given by the teachers, and never considered what was wrong, why it was wrong, and how to correct it. As a result, every time I make a mistake here or there, I can't get full marks. Once, my math teacher said to me:? When we learn knowledge, we should really understand it. You can't just look at grades and scores. If the question is wrong, carefully analyze the cause of the mistake. I suggest that each of you prepare an error correction book, copy down the types of wrong questions, find out the reasons for the mistakes, and correct them seriously. ? From then on, I prepared a small notebook the size of a palm and wrote three words on it? Correct the wrong book? .
Whenever exercise books and papers are handed out, I always analyze them carefully and copy the wrong questions in? Correct the wrong book? In fact, carefully analyze the cause of the error, mark the wrong place with a red pen, and seriously correct it. For example, when I was learning to solve equations, my? Correct the wrong book? It's in the newspaper.
Grade 2 math diary 7
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 egg, and the hummingbird mother lays 2~ 1 egg at a time, which is only the size of a bean, each weighing 0.5g About 200 hummingbird eggs are the size of an egg. Hummingbirds can fly out of the nest for food and start an independent outdoor life after living for about 20 days.
What interesting knowledge, it can not only learn, but also increase extracurricular knowledge. It really kills two birds with one stone.
Grade 2 math diary 8
This morning, my mother took me to the supermarket of Falian for shopping. When I arrived at the store, I didn't know what to buy because of the dazzling array of goods.
First, we came to the gourmet area. I chose Shanghaojia natural potato chips and Mengniu dried milk tablets, and my mother chose a bottle of vitamin chewable tablets for growth and happiness.
Then we went to the electrical area and bought a Runxin repeater. Finally, we went to the daily necessities section and bought a San Xiao toothbrush.
It was then that my mother remembered that she had only one hundred dollars with her, and I didn't know if it was enough.
I looked at all the commodity prices: Shanghaojia natural potato chips 4.8 yuan, Mengniu fresh milk dried tablets 13 yuan, San Xiao toothbrush 3.5 yuan, growth-happy vitamin chewable tablets 29.9 yuan, Runxin repeater 62 yuan. Then I estimated that it would be 1 13 yuan. I quickly told my mother that there was not enough money. We'll put the Happy Growth Vitamin Chewable Tablets back.
Fortunately, I learned to calculate this time, otherwise I would make a fool of myself!