cause
In autumn, we went out to look for leaves. The children's enthusiasm for playing leaf games is very high, and their little heads are full of all kinds of question marks:
Why do leaves turn yellow?
Why do leaves fall?
Why do some trees shed leaves and some trees don't?
develop
In order to solve the children's doubts about autumn leaves, on Wednesday, the teacher brought two celery from home, ready to guide the children to understand the law of plant water absorption and growth. Celery experiment is an interesting visual experiment. Through observation, children can understand how plants absorb water and grow. In order to make the experimental phenomenon more intuitive, food pigment was added to the experimental water to make the net water absorption of celery more obvious.
In the activity area, under the guidance of the teacher, two children personally made a "home" for celery.
First cut off the mineral water bottle, then pour in an appropriate amount of water, drop 3-4 drops of food pigment respectively, stir the color evenly with a cake fork, then put it on the top of the mineral water bottle to help better fix celery, and finally put in two prepared celery trees.
The next thing to do is to continue to observe and record. Every day, children will come to the natural corner to observe and record the changes of celery in the activity area and after meals. For the convenience of recording and expressing, the children named the two celery "Daqin" and "Qin Xiao" respectively.
Through this experiment, we help children understand the water absorption principle of plants. Plants absorb water through roots, and water is transported to all parts of plants through pipes in plant mirrors, which provides conditions for photosynthesis of plants. When food pigment is added to water, it will enter the celery mirror with the water and then enter the leaves. By eating pigments, we can clearly see that water is transported to all parts of plants.
Experience transfer
After understanding the water absorption principle of plants, let's go back to the question of why big trees fall leaves, so that children can better understand. In autumn, the temperature drops, the rain decreases and the weather is dry, so the roots of big trees can't absorb so much water. If you keep the leaves, you will consume a lot of water, which may threaten the life of the whole tree, so the leaves will dry up and fall off. But after cold and drought, new leaves will grow back.
Activity expansion
When children understand that defoliation is to make trees survive better, stimulate children's love for trees, and thus promote the process of theme activities, they naturally come to participate in the activities of "I love mother trees" and "protect mother trees". Our Class 2 came to the outdoor venue of the kindergarten and adopted a five-pointed maple. Kiss the tree, hug the tree, and give this pentagram a nice name. "Teacher, call Doudou!" "Teacher, call little red! Because its leaves are so red! " ..... Finally, we named this tree "Niu Niu", because this year is the Year of the Ox, and children hope this big tree can be as powerful as an ox! Some children said, "Brave Niu Niu is not afraid of difficulties!" Slogan. Then in the activity area, the children drew a famous brand for the tree. Our story with Niu Niu has just begun. ...
Reflection:
In this small scientific experiment, because the celery selected is not very fresh, the experimental effect can be shown but not obvious enough, so more experiments can be carried out. In this process, we can take the opportunity to stimulate children's attitude towards experiments, that is, to succeed in constant failures, to improve children's ability to resist setbacks and to increase their interest in scientific experimental activities.