Activity objectives:
1, understand the different sinking speeds of paper boats with different textures in the water.
2. Learn to describe your findings in words.
3. Have the consciousness and ability of division of labor and cooperation.
4. Cultivate children's curiosity about things and be willing to explore and experiment boldly.
5. Develop children's observation and imagination.
Activity preparation:
1. Material preparation: rice paper, newspaper, boats folded with paper, one basin for each group, one tray for each group, one pen for each child, collective record sheet and group record sheet.
2, experience preparation: know several common papers in life, know that paper can absorb water.
Highlights and difficulties of the activity:
Can carefully observe the subtle changes of paper when absorbing water, and can describe its findings in words.
Observe and record the cooperation between children.
Activity flow:
1, the beginning part: stimulate children's interest and arouse their thinking.
(1) The problem situation of "three boats absorbing water" caused children to guess the phenomenon of "paper absorbing water at different speeds".
Teacher: Please look at what's on the table.
Child: the boat.
Teacher: Please have a look and feel it. What paper are these three ships made of?
Children: newspapers, picture paper, rice paper.
Teacher: This is very common around us. Paper absorbs water. Can these three paper boats absorb water?
The children answered "yes" without hesitation.
Teacher: Will the boat change when it absorbs water? How to change it?
Children: rot, sink and disperse. ...
Teacher: Do they change at the same speed? (Most children have different guesses.)
Teacher: Who do you think will change first? Who will become the second and who will become the third?
The children speculated that ...
Teacher: How can we prove whose point of view is correct?
Children: use experiments to verify and check information. ...
Teacher: Today, the teacher prepared experimental materials for the children, and later they will be allowed to do experiments by themselves.
(2) Teachers show the group record form and discuss with children how to record their own guesses.
Teacher: How to record the order in which a ship sinks into the water?
Children: The first one draws a tick, the second one draws two ticks and the third one draws three ticks.
(3) Discuss in groups and record the results.
2. Explain the experimental rules and cultivate children's sense of cooperation.
Every two children are a group, put three boats into the water at the same time, two people observe together, and one person acts as a recorder. When the ship is found to have changed, the recorder shall record the results in time.
3, children's division of labor and cooperation, guide them to observe the change process of the boat and explore its reasons.
(1) Guide the children to observe the changes of the boat.
Teacher: What did you find?
Child: The boat folded with rice paper is wet.
Teacher: How do you know it is wet?
Child: It gets wet as soon as you put it in the water. It changed color. It has a line, which looks a little wet from this line.
Teacher: Why is it wet?
Child: Because it absorbs water.
(2) Inspire children to think that different ship materials are the reasons for different sinking speeds.
Teacher: Do they both absorb water?
Child: No.
Teacher: Why not? How do you know that?
Child: The rice paper has changed color, but the drawing paper and newspaper have not changed.
Child: Look, the rice paper has become soft and heavy, while the drawing paper and newspaper are still hard (the child fished out the soaked rice paper boat from the water).
Teacher: Why is the rice paper soft and the other two boats still hard?
Child: Because rice paper absorbs water more quickly, newspapers and drawing paper absorb water more slowly.
4. Share the experimental results.
Show the record form of each group, and ask one child in each group to talk about the experimental results of their own group. The different water absorption speed of toilet paper leads to different sinking speeds of ships made of various papers. "This key point guides children to explore in depth. The teacher's thinking is clear, the questions raised are very hierarchical and deep, and he always focuses on the goal in the activity.
Early guessing can fully arouse the interest and enthusiasm of children's verification, and children behave naturally, positively and happily, which reflects the good educational routine of the class.
Materials are prepared by teachers in advance, and closed materials limit children's exploration opportunities. Children should be allowed to collect all kinds of papers to make their own boats, and then let them compare and verify each other. Secondly, the guessing part should dig out the children's thoughts in time and let the children talk about the reasons for guessing again. Avoid children guessing.