First, hands-on operation can stimulate students' interest in learning.
Interest is the best teacher. Interest has a great internal driving effect on students' learning. Edison, a famous scientist, once said, "I have never made accidental inventions. All my inventions are the result of careful consideration and rigorous experiments." In teaching, let students spell, swing, fold, cut, measure, draw, think and speak, and give students as many opportunities as possible to start, use their brains and speak. Hands-on operation is an effective and best way to stimulate students' interest in learning.
For example, when Mr. Zhang Wenjuan talks about axisymmetry, let students prepare scissors, cardboard and other appliances, so that they can freely use their imagination in class, fold and cut out their favorite graphics, and discuss and appreciate them. Then combined with textbooks to understand the concepts of symmetry axis and symmetry point, students can learn knowledge very easily.
Second, hands-on operation can make students realize the sublimation of knowledge.
Hands-on operation is both hands-on and brain-use, which not only opens up the space for thinking and imagination, but also helps students understand knowledge points from different angles and directions, deeply appreciate the ubiquitous charm of mathematics, and realize the truth that "learning is everywhere"
For example, when teachers and Miss Li are studying congruence of triangles, they all ask students to make different plane graphics with two congruence triangles, observe the changes of graphics and various graphics, understand the nature of congruent triangles, effectively stimulate students' interest, and master the internal relationship of congruent triangles in the process of playing and doing. In short, from simple to complex, students can actively observe, operate, reason and imagine the exploration process. Through such repeated practice and exploration activities, students can truly realize that "knowledge comes from life practice".
Of course, consolidating exercises is also an important part of mathematics teaching. In teaching, according to junior high school students' cognitive rules and thinking characteristics, we should cultivate students' hands-on operation ability, let students operate by themselves (draw scalar spells and guess), and apply the mathematical knowledge and skills, mathematical ideas and methods learned in class to solve practical problems. This method can not only save time greatly, but also improve the efficiency of solving problems, especially in exams, which can be of great help to students.
Third, hands-on operation can develop students' thinking.
Thinking begins with action, and hands-on operation can help students gain perceptual knowledge and provide a pillar for their thinking. Students are in the transition period from concrete thinking to abstract thinking, so it is not easy to understand and master abstract contents such as mathematical concepts, theorems and rules. Therefore, strengthening intuitive demonstration and hands-on operation in the teaching process will increase students' perceptual knowledge and form vivid images in their minds, which is conducive to their understanding of abstract mathematical knowledge.
Such as; In the lesson "Comparison of angles", students have mastered the general method of measuring angles and drawing with protractor. How to draw an angle of 120 degrees, most students use protractors and triangles to draw. The teacher asked: How can you draw without a protractor? Students immediately entered the pleasant operation with questions, and soon found two drawing methods: (1) put together a right angle and a 30-degree angle of a triangle. (2) Put them together at two 60-degree angles. Students found a way through their own thinking and gained the joy of success. Then the teacher asked again; Is there any other way? At this time, the students are more enthusiastic, scrambling to start exploration again, and found that first draw a right angle, and then draw a 60-degree angle with a triangle on the basis of this right angle (that is, 180 minus 60 degrees). Finally, I asked how many degrees a triangle (integer multiple of 15) can be drawn. This can provide students with practical opportunities as much as possible, so that their thinking can be developed, their knowledge can be sublimated, and their practical ability and thinking ability can be developed and improved.
Therefore, in classroom teaching, we should provide students with more opportunities to operate, encourage students to seek differences and innovate, and further develop students' ideas. In the process of hands-on, students not only mastered knowledge, but also improved their thinking ability.
Fourth, hands-on operation must let students develop hands-on habits and develop their "re-creation" potential.
Practice produces true knowledge, and practice is the cradle of innovation. Through hands-on operation, students can not only cultivate their ability to solve problems, but also cultivate their innovative ability. In traditional teaching, students are often required to memorize basic concepts and knowledge. Now, through hands-on operation, we should actively guide students to pay attention to the actual background and production process of concepts, let students know the ins and outs of concepts, deepen their understanding of concepts, and cultivate the rigor of students' mathematical thinking. Every class, whether algebra or geometry, has the cultivation of students' practical ability, and students will naturally develop good practical habits over time.
In the teaching of color graphics, multimedia courseware can be made by using three-dimensional animation to explain various elements of geometry in a three-dimensional, vivid and intuitive way.
In the teaching of "irrational number", it is found that the side length of a square can be expressed by a number that we have not learned, which leads to the concept of irrational number. In the process of students' independent exploration, students have a deep understanding of irrational number knowledge and left a deep impression. While enlivening the classroom atmosphere, let knowledge really become students' own things.
Fifth, strengthen students' practical ability and actively acquire knowledge.
Hands-on operation will enable students to master knowledge easily and flexibly, and learn the methods and skills to master knowledge. The new curriculum standard points out that classroom teaching is a complicated process of multi-directional communication between teachers and students, and teachers are the leaders of the whole teaching process. Students should actively acquire knowledge through the inspiration of teachers, which is the basic point to improve classroom teaching effect. The method of using learning tools and teaching AIDS is to create an environment for students to explore and think, so that all students can participate in the activities of exploring new knowledge.
1. The purpose must be clear.
Students should have clear instructions before starting work, so that students know what to do. For example, when teaching the sum of the internal angles of a triangle, let the students guess that the sum of the three internal angles of a triangle is a fixed value. Ask the students to measure the degrees of the three internal angles of the triangle, and then add them up and find that the sum of the three internal angles of the triangle is 180 degrees; Then let the students make a triangle with any shape out of paper, tear off three internal angles and put them together. It is found that the spliced angle is a right angle. Then ask the students to sum up that the inner angle of the triangle is 180 degrees. Students draw conclusions in relaxed and pleasant operations; The sum of the internal angles of any triangle is 180 degrees. In this way, students can discover, think, comprehend and summarize by doing things, and actively acquire new knowledge through active participation.
2. The hands-on process must be orderly.
In the process of hands-on, it is very helpful to form a clear thinking system by being methodical, clear in steps and advancing layer by layer. Students' cognitive law is from the beginning of graphics to the understanding of numbers, to the expression of symbols, and finally to the summary of algebra.
Reading and thinking of the first volume of the seventh grade of Shanghai Science Edition —— This is an explanation of the number of squares, the sum of n odd numbers and the number of lines that make up a figure in an inductive reasoning class. (Teacher Yuan reflected it in the lesson "Into the World of Mathematics" opened by the Canal. )
In a word, the cultivation of hands-on operation ability is the implementation process of students' comprehensive quality from theory to practice in learning and applying mathematics. To improve students' hands-on operation ability, it is necessary to cultivate students to analyze and solve problems in depth by using the thinking mode of "observing with methods, operating with motives and thinking on the basis". This not only helps to visualize and concretize abstract mathematical knowledge, which is easy for students to accept, but also helps students to learn independently and truly become the masters of learning, laying a solid foundation for learning mathematics well.