He Ailing 1. Write school plans and guide preview 2. Create a situation and ask questions 3. Highlight the key points and break through the difficulties After the presentation of each group, everyone analyzed the advantages and disadvantages together. The students actively participated, discussed enthusiastically, boldly imagined, and actively spoke. Teachers and students analyzed together. In this process, they provided a stage for students to show their wisdom and intelligence, and cultivated their good ability to explore thinking. The students spoke actively and actively, using the large screen to compare and optimize the discussion results of the students, and the performance form was intuitive. Students discover the advantages and disadvantages of various methods, and then inspire students to better understand, master and discover the law, and try to solve the problem. The evaluation standard of the best plan is summarized: simple operation, obvious phenomenon, safety and environmental protection. 4. Self-study, display purpose 6. In-house inspection and homework assignment 7. "Zhongxing" was announced and praised and motivated references [1] Zhu Yue, Editor-in-Chief Yue Gangde. Concept and implementation of new high school chemistry curriculum [M]. Hainan: Hainan Publishing House, 2004 Comfity Memory Foam Mattress Queen conforms to your curves and hugs you to sleep. Comfortable memory foam distributes weight evenly to align the spine and alleviate pressure points. You can choose whatever the 2 inch thickness or 3 inch thickness, and the 3 inch Memory Foam Mattress queen will hug your body more than the 2 inch memory foam mattress queen. This is absolutely the good way to rejuvenate old mattress, and soften the hard mattress and prolong your mattress life. Memory Foam Mattress Queen Memory Foam Mattress Queen,Mattress Topper Queen Firm,Queen Mattress Topper,Queen Bed Topper Memory Foam Shenzhen Comfity Technology Co.,Ltd , https://www.comfitymemoryfoam.com
The Second Middle School of Yiyuan County, Zibo City, Shandong Province
On the basis of reading through junior high school textbooks, course textbooks, teachers' books, reference network resources and school resources, classify knowledge and formulate knowledge problems, problem levels, knowledge reserves, and suitable for their students. , That is, the case study method. And according to the characteristics of the chemistry subject and group tasks, typical examples, classroom testing and other content, set into a rational case. The study plan mainly uses the chart function of the Word file and is designed into three columns, as shown in Table 1:
Table 1
Send the "study plan" to the students 2 to 3 days before the class, so that the students have enough time to prepare, discuss and fill out. Then, by drawing and approving the school plan, the "school plan" will be supplemented and perfected again to grasp the true academic situation and grasp the key points of the lesson preparation. At the same time, the "Preview Star" was selected. When the courseware "Preview Star" is cast on the big screen and the students are holding their breath to try to find their name, the teacher will encourage the students who did not rate this time. As long as they work hard, they can do better next time! Then the big screen is revealed: according to the performance of the classroom, stars of wisdom, stars of activity, stars of display, stars of doubt, stars of innovation, stars of courage, stars of progress ...
Next, the nine group leaders led the group members to discuss the content of the study plan, find out the difficulties and doubts, and the student representative board played on the blackboard. Do not talk about the problems that can be solved by the students 'preview and discussion, reflecting the main role of the students' "teaching soldiers". Through the study of this lesson, students will learn to acquire knowledge with scientific learning methods and experience the fun of learning science.
According to the students' problems and the difficulties of this section, under the background of high mountains and flowing water and the background music environment, cast the content of this section-the nature of sodium, with rolling captions: "Tap your potential, cast great success, promote your personality, portray extraordinary "Life" "My classroom is my master, my life is wonderful" "Leadership comes from competition, success comes from cooperation" "I participate, I am happy, I grow" "Classroom is wonderful because of interaction, students develop because of independence" "Classroom On the big stage, everyone shows style. "Students are always inspired and their interest is high.
First of all, a short video "Life and Death Isolation in Firelight" was cast on the big screen. [Ask the question] Why did the presence of sodium metal in the fire make the firefighters feel terrible? Leave suspense and give students room to imagine. Watching the video clip caused doubts and aroused interest.
The reaction between sodium and oxygen, and sodium and water is the focus of this section. There are two characteristics of the fire scene in the short film: high temperature; general fire fighting measures are water, can this method be used? The author asks every 3 classmates to carry out experimental exploration activities and demonstration experiments.
First, a large screen shows a schematic diagram of the atomic structure of sodium. The schematic diagram of the atomic structure of sodium is made into a Flash file, highlighting the three-dimensional sense of the atomic nucleus and the arrangement of extranuclear electrons. Let students speculate the nature? Students actively spoke and teachers and students reached a consensus.
[Experimental exploration activity 1] Observation: Metal sodium is stored in a reagent bottle filled with kerosene, and the nature of sodium is predicted. Students first answer the perceptual knowledge, such as sodium metal is solid at room temperature, does not react with kerosene, and the density is greater than kerosene. After a deep thought, sodium may react easily with certain substances in the air.
[Experimental activity two] 1. Take a small piece of sodium with tweezers, dry the kerosene on the surface with filter paper, cut off one end of the skin with a knife, and observe the color state of the cut surface. 2. At normal temperature, observe the color of cut surface after a while. Students experiment and record phenomena. While waiting to continue observation, students are encouraged to complete the [demonstration experiment and physical projection while explaining the operation phenomenon] 3. Take a small piece of sodium in a hard glass tube, fix it to heat, and observe the flame color, product color and state when it is on fire. In this experiment, in order to facilitate the real project, the crucible in the textbook was changed to a hard glass tube. The reaction phenomenon after the enlargement on the booth is clear and obvious. At the same time, everyone observes the experimental phenomenon together, describes the experimental phenomenon, and shares the joy of the success of the experiment. Teachers ask questions in a timely manner, and students record phenomena and equations on school plans, and jointly break through the focus of the reaction between sodium and oxygen.
[Assumption Conjecture] Can the fire be extinguished with water? Sodium is very lively, will it react when it meets water? If reacted, what is the product? Students combined with knowledge analysis of redox reactions may produce NaOH and H2.
ã€Experimental Research Activity Three】 Each group designs an experimental plan based on the experimental purpose and provided instruments and drugs, hands-on experiments, and fills in the experimental report. After 5 minutes, each group will send a representative project to show the plan, operation, phenomenon, conclusion and result. The students mainly designed the following 4 schemes:
Then the big screen cast [teacher self-made teaching aid experiment video], re-strengthening the physical properties of sodium and the observation of the reaction between sodium and water, product inspection. Encourage students to make their own teaching aids and use manual brains. Works can participate in competitions and experience the joy of success.
[Looking back] Why did the presence of sodium metal in the fire make the firefighters feel terrible? [Injection data] Sodium metal will react violently when it encounters high temperature and water, and it can explode violently in a short time. Is there 10 tons of flammable sodium near the site? The student spontaneously said: terrible! The courseware is presented in the form of explosive graphics and sound, which is very powerful.
Fire fighting pictures: Firefighters used cold foam with less water to cover the fire. Students listen, why do you understand? Let students experience the fun of using chemical knowledge to solve difficulties around them.
[Guide students to learn independently] Read textbooks and complete questions.
If sodium catches fire, what should be used to extinguish it? How to save sodium? Can sodium exist in free state in nature? why? What are the main substances? What is the use of sodium?
The students actively stood up to answer and let students deepen their sensory understanding of the existence and use of sodium in the form of pictures.
V. Summary of nature, expansion and sublimation
Write the chemical equations for the reaction of sodium and oxygen, and sodium and water. It is the ion equation. If it is a redox reaction, make an analysis. Student role-playing, thinking and communication, questioning and questioning, teacher-student interaction, student-student interaction, embodies the pre-relationship of knowledge. Propose: What did you gain in this lesson? First let the students sum up, and then the teachers and students sum up to improve their ability. Cultivate the habit of being good at summarizing and cultivate scientific learning methods.
Then put the photos of David on the big screen. David electrolyzed the moist caustic potash in a closed crucible and finally got this silver-white metal. David threw it into the water. At the beginning, it turned rapidly on the surface of the water, making a hissing sound, and then burning with a lilac flame. He confirmed that he had discovered a new metal element. Since this metal is made from potash, it is named Potassium (Chinese translation is potassium). Later he used electrolysis to produce metallic sodium, magnesium, calcium, strontium, barium and non-metallic element boron, becoming the most discovered new element in the history of chemistry.
The teacher said in time: Great scientists have good qualities-David's success is due to his rigorous scientific attitude of careful observation and bold judgment, and the perseverance and courage to dare to challenge the authority without satisfying the existing achievements!
1. On-site detection: Set the exercise to a shooting game and present it on the big screen. The target and topic of the shooting are set as hyperlinks, and the students select the topic to answer the questions, eager to try, high interest and good effect.
2. Homework:
(1) Open interest experiment—water ballet: Put sodium into the mixture of benzene and water and observe carefully. Encourage students to go to open laboratories to complete interest experiments and exercise their practical ability.
(2) In the process of studying the properties of sodium metal, we have used many methods, such as observation, experiment, classification, comparison, design, optimization, etc., based on the knowledge and existing life experience to predict the physics of aluminum, iron and copper Properties and chemical properties
The class representatives announced the results according to the class performance. Each time a classmate was announced, the information technology class representative pointed the camera lens at him or her and cast it on the big screen at the same time. The "stars" had the pride and honor of movie stars. The classroom performance in the next class will definitely be better. Teachers praise and motivate them in a timely manner, let them use the classroom as a stage, study hard, continue to explore, think higher and fly farther.
[2] Editor-in-chief of Guo Sile. Education is moving towards being a student [M]. Beijing: People ’s Education Press, 2010
Exploring Students-based Classroom under the Condition of Information Technology
activity theme
Learning inquiry process
Summarize