Pupils can't learn to calculate, solve problems and understand geometric figures without concrete objects. In teaching, teachers can use teaching AIDS or audio-visual teaching to make teaching intuitive, but there are still limitations-students can only be spectators. If teachers guide students to operate learning tools timely, appropriately and appropriately in teaching, and let students participate in the cognitive process with their hands, brains and mouths, it can not only stimulate students' interest in learning, but also help students acquire and master new knowledge. Let's talk about some experiences by guiding students to operate learning tools in teaching:
1. operation is beneficial to students' understanding of geometric shapes.
Because of the age characteristics and cognitive rules of primary school students, teachers should be good at letting students operate learning tools more, and know the characteristics of things from intuitive perception, so as to acquire knowledge. For example, in the class of "Understanding Rectangles and Squares", in order to let students master the basic characteristics of rectangles and squares, teachers should let students take out their learning tools and count how many sides there are in rectangles and squares. How many angles? Then ask the students to measure the length of each side of a rectangle and a square with a ruler. What are the characteristics of measuring the length of each side of a rectangle by hand? What are the characteristics of side length? What are the characteristics of the length of each side of a square? Then ask the students to compare each corner of a rectangle and a square with a right triangle. Through students' hands-on "counting", "measuring" and "comparing". Find out the characteristics of corners and sides by yourself, so as to sum up the characteristics of rectangles and squares and their similarities and differences. This teaching method not only stimulates students' interest in learning and makes them love and enjoy learning, but also enables students to discover and summarize the characteristics of geometric shapes, so as to remember new things and master more profound knowledge.
Second, the operation is helpful for students to master the calculation formula of plane geometric figure area.
To master the calculation formula of plane geometric area, the key is to let students understand the source of the formula. The calculation formula is based on the knowledge that students have mastered. Therefore, when imparting knowledge, teachers should guide students to transfer old knowledge and let students operate learning tools in a timely and reasonable manner. From the observation and analysis of operating tools, the internal relationship between new knowledge and old knowledge is found. Thus, the area calculation formula of plane geometric figure is deduced.
Thirdly, operation helps students to understand arithmetic and master calculation methods.
The development of junior high school students' thinking is inseparable from the concrete operation of learning tools. In teaching, teachers should try their best to create more opportunities for students to move learning tools, and help students find and understand arithmetic from operating learning tools, so as to master calculation methods.
4. Operation helps students to improve their ability to answer practical questions.
Because the thinking of primary school students is in the transition stage from concrete image thinking to abstract logical thinking. Their abstract thinking process naturally needs the support of concrete images. Timely and appropriate operation of learning tools in teaching can develop students' thinking and help them solve practical problems such as spelling and cutting abstract geometric shapes. For example, after teaching the surface area calculation of cuboids and cubes, there is an exercise: "It is known that two cubes with a side length of 3 cm are combined into a cuboid. What is the surface area of this cuboid? " Solving this problem requires spatial imagination. Because of the poor spatial imagination of minority students, in order to guide students to understand the problem correctly, teachers can ask students to take out two cubes with the same size when guiding students to practice, so that they can spell, think and talk about the relationship between the length, width and height of the spliced cuboid and the side length of the original cube. It is not difficult for students to draw that the surface area of a cuboid is (3×2×3+3×2×3+3×3)×2=90 (square centimeter). At this time, we guide students to analyze from different angles, and then we get that the surface area of a cuboid is 3×2×3×4+3×3×2=90 (square centimeter), 3× 3× 6× 2-3× 3× 2 = 90 (square centimeter), and 3×3× 10=90. Then guide students to compare several algorithms, which one is simple and reasonable. Through discussion, the students all have a purpose. It is recognized that 3×3× 10=90 (square centimeter) is the simplest and most reasonable algorithm. It can be seen that in teaching, instructing students to operate learning tools in time can help students analyze and think from different angles, find out the characteristics of things, find simple and reasonable algorithms and solve problems correctly.
5. Operation helps to improve students' thinking ability.
Action and thinking are inseparable. Junior students are particularly interested in new things and like to move and try. Therefore, in teaching, students should be provided with colorful intuitive materials that can highlight the characteristics of knowledge, "do what they like", and let them do it by themselves and feel the practice. For example, when teaching "division with remainder", students can be organized to wear colorful sticks. Take out the wooden stick of 10 first, and put a square on every four wooden sticks. How many squares can you put? How many sticks are left? And list the corresponding division formula, and write down the remaining number of sticks, and then let students take out 1 1 sticks to 15 sticks respectively, imitate them one by one, and write them on the blackboard to strengthen training and make their procedures standardized and skilled. Through the coordination of action and perception, action thinking is constantly promoted, so that students can initially understand the generation and significance of remainder and summarize the concept of remainder. This can guide students to discover, think, comprehend and generalize from their own behaviors, gain intuitive knowledge and promote the development of thinking.