The weather is nice today. It is rare to have warm sunshine in winter. After lunch in the afternoon, I took the children to the front playground to play on the slide. The children were having so much fun like wild horses running wild, climbing up and down, or chasing after each other. At this time, I found child Qiaoqiao squatting quietly next to the slide, tinkering with a little child on the tree stump. Puddles. I went over and observed it for a while, and saw her tearing up a leaf and gently putting it into a small puddle, and then tilted her head to observe the small puddle. I thought she was "cooking delicious food" and playing house games, but I didn't say anything directly. Instead, I asked tentatively: "Qiaoqiao, what are you doing?" Qiaoqiao replied: "I'm observing why the leaves are there." Floating on the water? "It turns out that I guessed wrong. Children's world is always unpredictable, and it is their unique ideas that often surprise us.

So I stopped and wanted to record Qiaoqiao’s exploration and discovery of nature. After a while, Qiaoqiao asked me again: "Teacher, why do leaves float in the water?" I said: "What do you think is the reason?" She thought for a while and said: "Because the water is too heavy. The leaves are too light!"

I did not rush to explain the answer, but asked her to try again to see whether other objects would float or sink in the water.

After a while, she found a small branch, broke it and put it into the small puddle, and found that the branch sank. I found a few dried redbud fruits and put them into the small puddle, and found that they floated up.

I recorded Qiaoqiao’s entire game process. She played around this small puddle for half an hour. In response to Qiaoqiao’s exploration of the phenomenon of sinking and floating, I naturally generated a scientific activity for collective use. During the teaching, I first showed the children a video of Qiao Qiao playing in a small puddle, and then asked the children to say: "Why do leaves float on the water?" Some children said the same thing as Qiao Qiao, and the Congcong child said: "Because the density of water is greater than that of leaves!" Finally, I explained to the children from a scientific perspective that there are many pores in the cells of leaves, and there is a lot of air in the pores. At the same time, under the action of the molecular tension of the water surface, the leaves become Can float on water!

Then I asked again: "Does it mean that as long as the leaves are leaves, they will float up?" The children answered in unison: "Yes!"

I smiled and took out the Make a cup of tea in advance and ask the children to observe, "Tea leaves are leaves on the tea tree. They sink when they are put into the water. Why?"

The children began to move thoughtfully. After thinking about it, some said: "Because the tea leaves have been soaked in water for a long time." Some said: "Because the tea leaves have been dried in the sun." I was very pleased to see the children thinking seriously. Finally, I explained: "The difference lies in whether it can be soaked. There is a layer of vegetable wax on the surface of fresh leaves, and water cannot enter the fine structure. Tea leaves will float when they are just put into the water without stirring. But because the tea leaves have been dried and processed, It will be soaked and sink quickly. If done well, a penny can also float on the water surface."

A lively and interesting science activity is generated from the children's Angie game. .