This week we entered "Wow, everyone has grown up!" The first unit of this topic, this unit is mainly to let children know that the change of time has changed personal changes (height, ability, etc. ) Through physical changes, personal space-time coordinates are established, and cognitive methods and habits of space-time contact are formed.
My teaching content is to measure the evidence of growth-the understanding of centimeters.
Before knowing the length unit of centimeters, there was a pre-class lesson in the small bamboo shoot class, which mainly talked about the beautiful ruler on the body.
The question leads to: How did people measure before the ancients invented rulers?
1. Measure the length of clothes with "".
Open five fingers of a hand, usually the distance between the end of thumb and middle finger is called a foot. The ancients measured the length of clothes in units of one foot.
2. Use "measuring long rope".
If there is a long rope in front of you, people don't want to use the standard of "square" to measure it, so the ancients came up with a way. The distance between two hands is a square, so the length of the rope can be measured by a square.
3. Measure the road length with "step".
I want to know how long this road is and how to measure it. People are not measured step by step, nor do they choose to lie on the ground. People choose "step" as the standard.
Finally, through the picture book My Beautiful Ruler, I learned more about the physical ruler. Children use the physical ruler to measure my home.
1, feel the necessity of unifying length units.
In the first class, teacher Beibei led bamboo shoots to find a lot of evidence of growth and continued to find evidence of growth. This lesson begins with Xin Tong's two trousers of different lengths, which is evidence of Xin Tong's growth. Xin Tong and I both measure the same pair of trousers in feet. Xin Tong's measurement result is 5 "and mine is 3". Why is the same pair of trousers measured in "feet", but the measurement results are different?
That's because this beautiful ruler on the body will grow bigger with personal growth. Because everyone's size is different, it is troublesome to express how long pants are. Children feel the necessity of unified measurement standards, which leads to the learning content of this lesson-"Understanding of centimeters".
2. Construct the concept of 1 cm length.
The understanding of centimeter is the first unit of length in primary school mathematics, so it is natural to establish the concept of 1 cm for children from 1 cm. By watching a series of teaching activities such as 1 cm- gesturing 1 cm- thinking 1cm- finding from life 1cm, let the children establish the appearance of 1cm. Then let the children feel the process from 1 cm to several centimeters. Here, the children measure the growth mark (the length of the middle finger of the fingerprint) with a stick with a length of 1 cm, and feel that several centimeters are composed of multiple 1 cm.
3. Learn a ruler.
Children all know that a few centimeters is made up of many 1cm, but it is very troublesome to make 1cm and 1cm into several centimeters, and connecting the sticks of 1cm one by one is like a ruler, so rulers are produced, so rulers are made up of many 1cm.
Knowing the origin of the ruler, we should carefully observe what is on the ruler.
Number: 0 on the ruler indicates the starting point.
Scale marks: long and short.
CM: stands for centimeter, which is the initials of English centimeter.
Knowing the ruler, children will look for 1 cm on the ruler. The children found that the distance between two adjacent numbers was 1 cm.
Finally, we also found that the scale from scale 0 to scale is several centimeters, which reflects the convenience of numbers and scale lines on the scale and paves the way for measuring the length of the object next.
Measure the length of this object with a ruler. (Estimated ruler)
The measurement object we choose is a stick familiar to children. In order to give children a sense of number and awareness of estimation, before measuring, guide children to estimate the approximate length of the stick with 1 cm as the standard, and then measure.
Pay attention to "1" when measuring, and the measured object should be flat. 2. One end of the object corresponds to the 0 tick mark. 3. Look at the other end of the alignment scale, which is a few centimeters. "
5. Learn the knowledge of broken ruler and measuring line segment.
For the study of broken ruler, the child's learning state has reached a climax, and the child finally understands that it is necessary to manage the beginning and see the end, and can't blindly draw conclusions.
I also hope that children can express their views in future classes and reflect on themselves from others' views, because the truth is not always in their own hands. Children should learn to listen-express-compromise-adjust and finally understand the truth of the problem.
Especially more grinding than grinding people. The lesson plan has been revised and adjusted again and again, but I also deeply feel that the reflection and revision after polishing have made my teaching process more compact and reasonable, the language in the classroom more concise, the instructions more clear, and I have gained a lot.
Thank the school for providing the opportunity to show the class; Thanks to the reflection and growth brought by the children's classroom performance; Thanks to the teaching and research group for making teaching AIDS and learning tools, giving lectures and discussing two pilot classes; Thanks to the teachers who came to attend classes, evaluate classes and guide the preparation of lessons for these good suggestions.
Taking children to heart, I will continue to learn to reflect in the future, so that real learning can take place in every class, and growth is still on the way. Let's work together!