(A) to stimulate interest stage
Students who have just come into contact with biology in senior high school have a strong curiosity about the mysterious micro-world, ever-changing biological phenomena and high-tech biology. If this curiosity can be transformed into curiosity, it is the internal motivation to promote students' active learning and the necessary condition for the development of creativity. In biology teaching, teachers should be good at grasping students' curiosity and transforming their thirst for knowledge.
For example, when talking about photosynthesis, the author asked students to do an experiment: making photos of leaves. The students immediately became interested and the classroom atmosphere became active. The teacher instructed the students to fix the negative of their photos on the tender leaves of plants (such as geraniums) in flowerpots, so that the plants could carry out photosynthesis in the sun. After two or three days, pick the leaves with negatives, remove the negatives and put them in boiled alcohol. What will you see? Students will see the green pigment dissolved from the leaves. The teacher asked, "What does this mean?" Through discussion, we come to the conclusion that pigment is soluble in alcohol. Then take out the faded leaves, remove the floating color, put them in an incubator, drop iodine solution, and you will soon see photos on the leaves. Ask the students to think about the reasons. Students read books quickly and seek answers. Through the discussion and active speech of the students, I found the answer. It turns out that each part of the negative has different shades of black and white and receives different light, so it is dyed with starch and iodine more or less, so there is a portrait. Students are interested in learning the knowledge of photosynthesis, and their thirst for knowledge is greatly stimulated.
(2) Perception stage
Textbooks are systematic book knowledge and practical experience of others. Students can only rely on their own life experience or related perceptual knowledge to understand book knowledge. In other words, when constructing new knowledge, it should be linked with the old knowledge in students' minds to form an effective transfer. In the process of guiding students to perceive textbooks, students' divergent thinking can be cultivated.
For example, when talking about the absorption and utilization of water by plants, the author designed a series of questions: How do plants drink water? Why is it good to enjoy the cool under the big tree? Why should some branches and leaves be removed when transplanting trees? What are the applications of osmosis principle in life? Learning the knowledge in books with these questions can make students quickly perceive the teaching materials and cultivate divergent thinking.
(3) Understanding stage
If teachers always talk about textbooks themselves, unify students with their own understanding and influence students, it will not only make the classroom boring, but also make it difficult to learn from students in the teaching process, which is not conducive to teaching and learning from each other. On the contrary, if we can listen to students' understanding and feelings about knowledge, teachers will be deeply impressed by students' innovation, and will also have new experiences in teaching and stimulate their teaching enthusiasm under the inspiration of students. For example, when studying the basic characteristics of living things, the author points out that there are all kinds of living things and many non-living things in this colorful nature we live in, but do you know their essential differences? Can you distinguish them well? Why do sunflowers always follow the sun? Why do mimosa close shyly when touched? A seed will grow into a towering tree, a stick insect will grow like a stick, a caterpillar will have poisonous fur, and a chameleon will change its fur with the change of environment. Why? Through the discussion between teachers and students, not only the enthusiasm of teachers and students is mobilized, but also teaching and learning learn from each other. Students understand and master what they have learned with full enthusiasm.
(4) consolidation stage
Some teachers think that consolidating knowledge is students' own business, and teachers only have the responsibility of supervision and inspection, but it is not. Teachers conscientiously sum up and sort out knowledge, and through students' thinking processing activities, it is helpful for students to sort out knowledge clearly and remember it well.
In biology teaching, the author tries to guide students to consolidate their knowledge with general memory method, and the effect is very good. Generalized memory method is based on the principle of meaning memory method, and on the basis of analysis and understanding, it summarizes the memory content of teaching materials, generalizes more memory content into several words or words (abbreviated as keywords), and memorizes keywords. When recognized or reproduced, the memory content is associated with the keyword. It is best to assign students the task of summing up their memories, so that students can sort out, process and summarize what they have learned, and at the same time, they can enhance their thinking ability. For example, when a student remembers the unity and difference between the biological world and the non-biological world, he summarizes the unity with "you have me" and the difference with "you are more than me". For another example, when consolidating the characteristics of four periods of mitosis in higher plants, a poem was compiled to remember and understand (the membrane nucleus gradually disappeared into two bodies, the number of equatorial order shapes was clear, the number of two poles split increased, and the two disappeared into two new walls).
(5) Application stage
The application of knowledge in biology teaching is mainly reflected in training students to complete a certain number of exercises. Through students' flexible application of knowledge in solving problems, the purpose of cultivating divergent thinking and logical thinking is achieved. For example, after learning the "metabolism of three nutrients", the author raised a question: Why does a person drink nothing for two days and still pee after eating dry food? Although this question is not very elegant, it is very appropriate and true because it is combined with real life, and it also consolidates this part of knowledge.
(6) Master stage
If teachers always pursue memorization and standard answers when conducting exams and tests on students, students will only see through the exams and get tired of them, and will not achieve the goal of cultivating students' ability at all. On the contrary, if you let students think and teach them to discover, they will naturally be happy and eager for exams. Now the college entrance examination questions are gradually reflecting this point.
References:
[1] Lv Chongmei. On the cultivation of innovative ability in senior high school biology teaching [J]. Success (Education), 2007, (8).
[2] Huang Yulan. Cultivation of students' innovative practical ability in biology teaching [J]. Science and Technology Information, 2007, (2).
[3] Dai Xiaoting. Cultivation of students' innovative consciousness and ability in biology teaching [J]. Shaanxi Education (Executive Edition), 2007, (2).