Teaching plan of unit 1 "water" in the first volume of science in a primary school: how many substances can water dissolve?
Teaching goal, scientific concept goal
1. Water can dissolve salt and baking soda.
2. The same water can dissolve different amounts of salt and baking soda.
Scientific inquiry goal
1. The amount of salt and baking soda dissolved in the same water was studied by comparison.
2. The objects in water can be completely dissolved by stirring.
Scientific attitude goal
Learn to observe experimental phenomena in a comparative way.
Scientific, technical, social and environmental goals
Feel the dissolution in life and know that you can use this change to serve your life.
Emphasis and difficulty in teaching
Key points: It is found that different substances have different solubility in water.
Difficulties: Learn to study the corresponding problems by means of comparative experiments.
Teaching preparation
Prepare for students: 20g of salt, 20g of baking soda, 8g of spoon and ruler, 2 beakers with 50ml of water, 2 glass rods, one white sugar, one monosodium glutamate and one brown sugar, a student activity manual, a summary table of class materials, etc.
Teacher preparation: a set of experimental materials for students.
teaching process
First, focus: reveal the topic (default 5 minutes)
[Material preparation: 1 salt, baking soda and alkali, 1 beaker filled with water, 1 glass rod]
1. Show me the salt and ask: What will happen if you put it in water? Students make predictions based on their previous life experiences. Default: disappear, disappear, dissolve. )
The teacher put the salt into the water and stirred it to dissolve it.
3. Question: Besides salt, do you know what is soluble in water? Students communicate and the teacher writes on the blackboard. Preset: white sugar, monosodium glutamate, brown sugar, etc. )
According to the students' answers, the teacher explained baking soda and alkali and showed them. (blackboard writing: baking soda, alkali. )
5. Question: If I keep adding salt to this glass of water, will it continue to dissolve? Where's baking soda? Can it dissolve all the time? (Students make guesses. )
6. Question: So, do different substances have the same solubility in the same amount of water? (Students guess. )
7. Secret topic: How many substances can be dissolved by water. (blackboard writing)
Second, explore: How much salt and baking soda can water dissolve (preset for 25 minutes)
Material preparation: each group prepares 20g of salt, with an average of 8 portions, 20g of baking soda, with an average of 8 portions (or 2g of salt, baking soda, spoon and ruler), 2 beakers with 50ml of water, 2 glass rods, student activity manuals and class materials summary table. (In the experiment, you can take 20 grams of salt and baking soda from the book and divide it into 8 parts; You can also use the flat spoon quantitative method, that is, use a 2 gram spoon to hold a spoonful of salt or baking soda, and scrape off the excess with a ruler. Teachers can choose according to the actual situation. )
1. Question: So, how can we know whether different substances have the same solubility in the same amount of water? If this class uses salt and baking soda to study this problem, how to study it? (Default: Students propose to conduct experiments. )
2. According to the students' opinions, show the prompt of group discussion in time: What should we do to know how much salt and baking soda can be dissolved in the same amount of water? Is there anything else to pay attention to? Students communicate in groups, discuss experimental methods and matters needing attention, and teachers patrol. )
3. The whole class communicates the experimental design scheme, and the teacher chooses the key words to write on the blackboard. (Default: same amount of water; Add the same amount of salt and baking soda each time, and then add the next time after the last time is completely dissolved. It is written on the blackboard: the amount of water is even, and the same amount is added every time. After completely dissolving, add the next one until it can't be dissolved. )
4. Read the science books on pages 13 and 14, and think about and communicate what else needs attention: Why is there so much water? How to add salt? When will the second and third copies be added? When do you stop adding salt and baking soda? How do you know that salt and baking soda are completely dissolved?
5. Teachers should give corresponding guidance and demonstration. (When using the flat spoon quantitative method, it is necessary to demonstrate how to obtain 2g portions of salt-use 2g spoon to hold a spoonful of salt, scrape off excess salt with a ruler, and the operating rules of stirring-when stirring, the glass rod should not touch the bottom and wall of the beaker, when to add the second and third portions of salt, record the dissolved salt in time, and how to judge whether the salt is completely dissolved. )
6. Show the third page of the activity manual to guide the students' experimental requirements and records: first complete the salt dissolution experiment, then complete the baking soda dissolution experiment, and make records according to the dissolution of salt and baking soda. When some salt or baking soda is completely dissolved in water, tick the table. The experiment is over, through statistics? To represent the amount of dissolved salt or baking soda.
7. Students divide into groups and record the amount of dissolved salt and baking soda. Teacher's patrol guidance, patrol notice: (1) whether the experiment is carried out according to the process; (2) Whether everyone in the group participates; (3) Whether the experiment is carefully observed and recorded in time.
8. After completing the experiment, students tidy up the equipment and summarize the class data on the blackboard or courseware.
III. Discussion: Experimental findings (5 minutes by default)
[Material preparation: data summary table]
1. Students observe the summary table of experimental data on the blackboard and exchange: How many parts of salt can 50 ml of water dissolve? How many portions of baking soda are there? (Instruct students to work out from the data on the blackboard, "How many parts of salt and baking soda are dissolved in 50 ml of water in most groups")
To sum up our findings, the solubility of salt and baking soda in water is different. Salt dissolves more than baking soda.
2. Organize discussion: Why should we join the above experiments one by one? What are the benefits of this growth? Students exchange ideas. Reach a consensus: Add them one by one, and you can clearly know how much salt and baking soda can dissolve in water. )
Fourth, expansion: Is the solubility of other things in water the same? (Default is 5 minutes)
[Material preparation: one white sugar, one monosodium glutamate and one brown sugar]
1. Teacher shows white sugar, monosodium glutamate and brown sugar. Question: If you want to know the solubility of these things in water, how to study them? Students exchange experimental methods. )
After returning home, students can use the experimental methods in today's class to explore the solubility of these substances in water.
blackboard-writing design
5. How many substances can water dissolve?
Salt, baking soda, sugar, brown sugar, monosodium glutamate and alkali. ...
Lesson plan of unit 1 "water" in the first volume of science in grade two or three: accelerate dissolution
Teaching goal, scientific concept goal
1. By stirring and raising the temperature of water, the dissolution rate of salt in water can be accelerated.
Scientific inquiry goal
1. The dissolution rate of the same salt in the same water was studied by comparison.
2. The objects in water can be completely dissolved by stirring.
Scientific attitude goal
Learn to observe experimental phenomena in a comparative way.
Scientific, technical, social and environmental goals
Feel the dissolution phenomenon in life and know that you can speed up the dissolution in various ways.
Emphasis and difficulty in teaching
Key point: Students realize that by stirring and raising the temperature of water, the dissolution rate of salt in water can be accelerated.
Difficulty: Design comparative experiment exploration.
Teaching preparation
Teacher preparation: a set of multimedia courseware and students' experimental materials.
Group preparation: 4 servings of salt, 4 cups of water (3 cups of tap water, hot water 1 cup), glass rod 1, stopwatch 1, student activity manual, etc.
teaching process
First, focus: reveal the topic (2 minutes by default)
[Material preparation: salt 1, a glass of water]
1. Show me salt and water.
Question: What happens when salt is put into water? (Default: Salt is soluble in water. )
Q: How long does it take for these salts to completely dissolve in water? (Default: 5 minutes, 6 minutes, 10 minutes)
Question: Who can make salt dissolve faster? (preset: stir with hot water and glass rod)
2. Reveal the theme: accelerating dissolution (blackboard writing)
Second, exploration: accelerate dissolution (preset 30 minutes)
Activity 1: How to conduct the experiment.
1. Organize students to discuss in groups: How can we know that mixing hot water with glass rods can speed up the dissolution of salt?
2. Organize students to report and communicate.
3. Teacher's summary: Comparative experiments can be used for research. When doing comparative experiments, only one of the conditions can be changed and the other conditions remain unchanged.
Activity 2: Explore the relationship between temperature and dissolution rate.
[Material preparation: 2 servings of salt with the same quality in each group, 2 cups of water (tap water 1 cup, hot water 1 cup), stopwatch, student activity manual, etc. ]
1. Question: What materials are needed to study the relationship between temperature and dissolution rate? (Default: salt, beaker, cold water, hot water)
2. Show me the experimental records.
3. Organize students to complete the above experimental records in groups.
4. Organize students to report and communicate.
5. Introduce the experimental requirements and filling methods of the student activity manual.
(1. Teamwork; 2. Step by step; 3. Record in time. )
6. Students are divided into groups to carry out experiments and complete the student activity manual.
Activity 3: Explore the relationship between stirring and dissolution rate.
[Material preparation: 2 copies of salt, 2 cups of water, 1 glass rod, stopwatch, student activity manual, etc. Each group has the same mass. ]
1. Question: What materials are needed to study the relationship between stirring and dissolution rate? (preset: salt, beaker, water, glass rod, stopwatch)
2. Show me the experimental records.
3. Organize students to complete the above experimental records in combination with the last experiment.
4. Organize students to report and communicate.
5. Students are divided into groups to carry out experiments and complete the student activity manual.
III. Discussion: Experimental findings (6 minutes by default)
[Material Preparation: Student Activity Manual]
1. Organize students to discuss in groups: What are the factors that affect the salt dissolution rate? how do you know
2. Students' feedback and communication.
Conclusion: By increasing the temperature and stirring of water, the dissolution rate of salt in water can be accelerated.
3. Question: Is there any other way to make salt dissolve in water faster?
Fourth, expansion: please continue to find ways to accelerate dissolution in your life. (Default is 2 minutes)
1. What methods do we know to accelerate salt dissolution through today's study?
2. There are more than two factors that affect the salt dissolution rate. Do you want to do experiments to study other factors that affect the salt dissolution rate?
blackboard-writing design
Accelerated dissolution
Comparative experiment: only one condition can be changed.
Method of accelerating dissolution: use hot water.
spread
The first volume of science in the third grade of primary school Unit 1 "Water" teaching plan: mixing and separation
Teaching goal, scientific concept goal
Students can understand that this change process is a reversible process through the fact that salt can be dissolved in water and separated from water.
Scientific inquiry goal
Students achieve the goal of separating sand from salt water by using filtration devices. The purpose of separating salt and water is achieved by evaporation, and finally the purpose of separating salt and sand is achieved.
Scientific attitude goal
By observing the characteristics of salt before dissolution and salt after precipitation, students can understand objects from multiple angles, thus forming a meticulous and objective observation attitude.
Scientific, technical, social and environmental goals
1. Through the separation of salt and sand, students realize the universality and importance of dissolution in people's lives.
2. For some mixed objects, scientific methods can be used to separate them to avoid discarding waste.
Teaching preparation
Prepare students: study list. Team preparation: 1 salt, 1 clean sand, 1 salt sand mixture, 1 glass rod, an alcohol lamp, a tripod, a box of matches, a filter cup and a beaker.
Teacher preparation: teaching courseware.
teaching process
First, focus on the task and reveal the theme (3-5 minutes by default)
1. Students watch the video. Is there any way to help uncles separate salt from sand?
2. Revealing the theme, mixing and separating
Second, guide exploration and scientific experiments (preset 25-30 minutes)
1.ppt shows pictures, and students can imagine and answer freely.
Student: One by one by color.
Students go to the stage separately, so that everyone can judge the feasibility together.
Health: according to the particle size, sieve it with a sieve.
Students go to the stage separately, so that everyone can judge the feasibility together.
Health: Put them in the water.
The students went on stage to pour salt and sand into beakers and stir them with glass rods to dissolve them in water.
Teacher: Then how do you get the sand out of the salt water?
Display filtering equipment
Teacher: Then how to remove the water from the salt water?
Display evaporation device
2. Task 1: Separate salt water from sand.
A. shows a filtering device.
B.ppt shows the process of dissolution and filtration.
C. students collect materials for dissolution and filtration experiments.
D. exchange of reports.
Teacher: What role does water play in this process?
Health: dissolve. (blackboard writing: dissolving and pasting)
Teacher: What role does gauze play?
Health: separate the sand from the salt water.
Teacher: that's filtering (blackboard writing: filtering and pasting)
3. Task 2: Separate salt from water.
A. understand the evaporation device.
B. students learn evaporation operation through micro-video.
C.Ppt shows the flow chart.
D. The teacher reminded the matters needing attention:
Wearing goggles can prevent salt water from splashing into your eyes when it evaporates.
② Do not touch the evaporating dish with your hands, and hold a tripod during finishing to prevent burns.
E. Students, experiments and exchange reports
Teacher: Where did the water go?
Health: evaporation (blackboard writing: evaporation, paste)
Third, think, discuss and discover actively (5 minutes by default)
Teacher: How can we help uncles separate sand from salt? (ppt)
Health: First dissolve the salt in water, then separate the salt water from the sand by filtration, and then separate the salt water from the water by evaporation.
Fourth, after-school expansion and knowledge extension.
Teacher: How can sawdust, iron filings and salt be separated when mixed together?
Lesson plan of unit 1 "water" in the first volume of science in grade four and grade three of primary school: what changes have taken place in them?
Through the study of the first seven lessons in this unit, we have a further comprehensive understanding of water and know what conditions water needs to freeze and melt. Students have rich life experience about the changes of some substances in life, and have learned about the changes of many objects in color, size and shape. They also know that although the size and shape of some substances have changed, the original substances have not changed. They have a certain understanding, but they have not yet formed a scientific concept. Through the teaching activities of this class, students can clearly know that although the state of matter has changed, on the whole, the composition of matter itself has not changed, and there are transformations among gas, liquid and solid. But the reason for the three-state change of water is still lack of concept.
According to the students' existing experience, this course aims to let students know that objects change in size and shape, but remain unchanged in essence, and use these characteristics to connect with real life.
Scientific concept goal
Although the state of some substances has changed, on the whole, the composition of the substance itself has not changed. Such as the three-state change of water.
Scientific inquiry goal
1. Use what you have learned to solve practical problems in life.
2. In the inquiry activities, discover facts, make judgments and develop thinking through speculation, observation, experiment and discussion.
3. Describe the results of observation and experiment with words, charts and pictures, and analyze the observation results.
Scientific attitude goal
1, forming a scientific attitude of respecting facts and attaching importance to evidence.
2. Develop a learning attitude that is willing to cooperate and communicate with others.
Scientific, technical, social and environmental goals
Recognizing that water is a very important resource on the earth has formed feelings, attitudes and values to protect water and air and cherish life.
Important and difficult
Observe and record the changes of three States of water and the changes of paper and plasticine; Discuss and exchange their similarities and differences.
Teaching preparation
Teacher preparation: video and teaching courseware of three-state change of water.
Group preparation: plasticine, round-headed scissors, white paper, student activity manual
teaching process
First, gathering: revealing the topic (7 minutes by default)
[Teacher's preparation: Show pictures of three-state changes of water in the courseware]
In winter, the water in the river freezes. When it is hot, introduce story pictures and add pictures related to the three-state change of water.
1. Question: What happens when ice melts into water? What happens when the water in the river freezes in winter? (Students presuppose according to previous experience: Students answer that water melts and becomes ice and liquid water. Water changes from liquid to solid when it freezes. )
2. Question: Thinking: When my mother was hanging clothes, the clothes slowly dried. What did the water on the clothes become? (preset: the water on the clothes disappears, the water on the clothes disappears, and the water on the clothes becomes the air running with steam)
The teacher made a supplementary summary according to the students' answers: Is the water really gone? In fact, after the water on clothes is exposed (heated) in the sun, liquid water turns into steam and runs into the air.
3. Q: What characteristics of water have changed? So is it still water?
【 Courseware shows student activity manual. Description requirements: record the observed phenomena on the table in the activity manual]
4. The courseware shows pictures of paper and plasticine. There are many changes in life, such as changes in paper and plasticine. At this time, pictures of paper products and plasticine products are presented to guide students to think.
Question: What happened to the objects in the picture? (preset: paper shape changes, balloon size changes, wood stick color changes, etc. )
5. Reveal the topic: "What happened to them"
2. Exploration: What happened to the paper and plasticine (preset 20 minutes)
Material preparation: 6 pieces of various papers, some plasticine, scissors, scraper, activity manual, etc. ]
Show courseware before the activity:
Activity requirements:
① Students can record the forms in the activity manual while doing experiments.
② Experimental conclusions can be drawn through analysis.
Activity question:
Question 1: What did we do to change the paper (plasticine)?
Question 2: Please tell me how they have changed.
Question 3: Is it the same as the original substance after the change?
Activity 1:
1, the teacher took out a piece of paper, folded out an origami model and made it simply.
(Pay attention to the time schedule and safety reminder when using scissors)
2. Students fill in the activity manual according to the above questions in the production process (the default for filling in the student manual is 1: origami, paper cutting, paper tearing, etc. Premise 2: Students can describe experimental phenomena according to experiments. Premise 3: Students can analyze experimental phenomena according to their own abilities. )
3. Communication and presentation: Ask students to explain their completed activity manual (default: students draw a conclusion according to their own data analysis that the paper has changed shape but is still the original paper. )
(After the presentation, put the materials back on the materials table so as not to interfere with the subsequent discussion. )
Activity 2:
1, provide plasticine and scraper, and let the students use this plasticine to make an item they like (pay attention to the time schedule and the safety reminder when using scissors).
2. Students should seriously consider three questions and fill them in the activity manual as required.
3. After completion, arrange to share the joy of finished products in the form of group stage display and communication. (Default: 1: pinch plasticine, scrape, rub, etc. Preset 2: color change, shape change, etc. Presupposition 3: Students analyze and summarize the experimental phenomenon that the shape of plasticine is preset to change but it is still plasticine. )
(After the presentation, put the materials back on the materials table so as not to interfere with the subsequent discussion. )
Teacher's question: Do you think about it? Are the plasticine works finished by everyone still plasticine? Is the changed paper still paper? (leads to the next link)
Three. Seminar: (5 minutes by default)
1. Q: We have observed many changes in this class. Are there any similarities? (Default: size change, shape change, etc. )
Teacher's instruction: Who is the water after it freezes? (Default: Student: Yes. ) Is it plasticine after being a clay figurine? (Default: Yes) In fact, we have one of the most similar similarities. Please talk about it. (Default: They are all the same substance. )
2. In the analysis and summary, it is concluded that although the state of some substances has changed, on the whole, the composition of the substance itself has not changed. Then compare the similarities of plasticine, water and paper: it is found that the change of the size and shape of the substance does not affect the essential change of the substance.
Four: Review and expand (8 minutes by default)
1, changes in life are happening anytime and anywhere. Do you know what changes have taken place around you? (Default: examples in life such as alcohol volatilization and firewood chopping. )
2. Review dissolution. The teacher is going to do a dissolution experiment. Ask the students to observe and talk about the relevance to the content in Lesson 4 and Lesson 5. Key points (preset: 100 ml water can dissolve 36 grams of salt, and the higher the temperature, the faster the dissolution and the smaller the particles. ).
3. Review mixing and separation.
Question 1: How do we separate sand from salt? (Default: sieving, dissolving, filtering, etc. )
Question 2: How is salt separated from water? (Default: sun exposure, heating, evaporation, etc. )
4. Understand the phenomenon of thermal expansion and cold contraction: the change of table tennis in exothermic water.
blackboard-writing design
8. What happened to them?
What phenomenon did the material see?
Changes in paper shape and size.
The shape, size and color of plasticine have changed.
Water morphological change
Similarity: it is still the original substance.