The accuracy of the comparison of size, length, thickness and height has been greatly improved. However, although children have accumulated a lot of life experience, they can't express it accurately in accurate language. At the same time, it is difficult to understand the relativity of quantity in the process of perceiving and distinguishing quantity. Distinguishing thickness is a common thing in our daily life. In the activity, let children compare the width of objects by visual inspection and overlapping, and let children compare the thickness of objects by touching and placing them side by side. At the same time, let children sort the quantities on this basis to help them understand the relativity of quantities. For the selection of materials, when comparing widths, use the same length of paper; When it is thick, choose books with the same length and width, so as to highlight only a certain amount of comparison, which is convenient for children to judge and distinguish correctly.

In life, when comparing two objects, we should compare them on the same plane. To understand the relativity of object thickness, teachers should consciously provide children with materials of different materials and shapes for comparison, so as to understand the comparison.

Based on the analysis of children's current age and the characteristics of teaching materials, after the activity, I made some thoughts on this activity.

1, the game runs through, so that children understand that width and thickness need to be compared.

At the beginning of the activity, I used the game introduction to attract children to compare the material. Simple paper card sorting games can not only guide children to explore the interest of materials, but also directly compare the width and thickness of themes. Finally, the game emphasizes the relativity of contrast.

In this activity, I provided rich materials.

Mathematics activities focus on letting children explore and find problems, think by themselves, exercise "learning by doing", exercise their thinking and expand their thinking through operation, and the rich materials in this activity provide children with opportunities for full exploration and thinking. Because of the rich materials, children can compare and find the width and thickness of objects through various senses. Find a way to compare by thinking.

3. Pay attention to the whole activity level.

Create two books on different planes, cover them with things, and arouse children's guesses. Then use the facts to let the children find that what they see is not true. So I know that two objects should be placed on the same plane when comparing. Secondly, I consciously provide different materials and different shapes for children to compare. On the basis of understanding the thickness comparison method, let them compare with various senses in a relaxed atmosphere to find the thickness between two objects. Finally, provide children with four pieces of paper with different materials and thicknesses, so that children can make full use of their senses and correct comparison methods to classify these papers.

4. Some problems appeared in the activity. You can appropriately extend the time for children to explore themselves. Because of the rich materials, children obviously have a very strong desire to explore by themselves, but the time for teachers to explore by themselves is too short, and children often end up in excitement and are taken to the next exploration link by teachers.