Hua, a famous mathematician in mathematics thesis, said: "The universe is big, the particles are tiny, the speed of rockets, the cleverness of chemical engineering, the change of the earth, the complexity of biological mysteries, and mathematics is everywhere." Especially in 2 1 century, the application of mathematics is everywhere. Then, how can we lay a good foundation in mathematics from an early age, and what kind of classroom teaching is suitable for the new generation of students? I think it is our wish that students play a leading role in learning in class. Then, math activity class is a teaching method that allows us to fully embody autonomous learning. In the activity class, under the guidance of the teacher, we explore and discover the rules in groups, and master the mathematical knowledge by measuring, piecing together, cutting and calculating by ourselves. This has cultivated our practical ability and improved our thinking ability. Moreover, it gives us a preliminary taste of the success of mathematicians in studying problems and doubles our interest in mathematics. For example, in our "Calculation of parallelogram area" class, the teacher asked us to divide into several groups and hand out some small pieces of parallelogram paper for students to discuss with each other. How to cut and paste a parallelogram into a graph whose area can be calculated? Everyone had a heated discussion. Some students found that parallelogram can be cut into right triangle and right trapezoid along its height with scissors, and then it can be spliced into rectangle. Some students also found that two right-angled trapezoids can be cut from any height of a parallelogram and can still be combined into a rectangle with the same size. Through observation and thinking, students realize that the "length" and "width" of the combined rectangle are the "bottom" and "height" of the original parallelogram respectively. So, everyone finally found the parallelogram area formula: S=ah. Teachers let students play poker games, so that everyone can quickly understand and master the calculation law of division with remainder, so that everyone can learn knowledge in relaxed and happy activities. Every time I do the Olympics, I always pick up a topic to do it, because I think it will be done quickly. However, when I was doing the Olympics today, a topic changed my view. It is not necessarily right to do it quickly, but mainly right. I made a question that stumped me today. I thought hard for hours, but I couldn't figure it out, so I had to look at the basic extraction and let it help me analyze it. The question is this: How many odd numbers are there in the square of 333333333? The analysis is as follows: the square of 33333333333 is 333333 * 333333. Because there are too many numbers, this multiplication formula is very complicated. We can simplify it by transformation, that is, one factor is enlarged three times and the other factor is reduced three times. The product remains the same. The problem turned into finding 99999999999 *1111111= (65438 1 1 1 1 1 1 1 1 1 1= 1 1 1 1 1 1 / Kloc-0/111000000000-11111. We can also calculate this problem by multiplying two numbers with fewer digits. You can find the number of odd numbers in the product, that is, 3*3=9→ there are 1 odd numbers in the product. 33*33= 1089→ There are two odd numbers in the product. 333*333= 1 10889→ There are three odd numbers in the product; 3333 = 1 1 08889 → There are four odd numbers in the product. After 1 and 8 respectively, the number of odd numbers in the product is the same as the number of 3 in a factor. It can be deduced that the product of the original problem is:1111165438+. I know we can't do math quickly. We need to know how to do it. In a word, I think it is very popular for us primary school students to have math classes in the form of activity classes. In class, every student is curious about the process of exploring knowledge and eager to find a solution to the problem through his own experimental activities. In learning, we fully realize the happiness and pride of being a master of learning. I hope teachers can take more math classes in the form of activity classes. So, we can