It is believed that, first of all, teachers should realize that primary school mathematics and secondary school mathematics must be related. Before preparing lessons, they should carefully understand the teaching content, what is the connection with primary school knowledge, which primary schools have studied and to what extent? From the perspective of primary school students, what do you think of the problems you are facing now? Of course, middle schools should cultivate students' self-study ability, so it is appropriate to let go. However, we should let it come slowly, and we must not ignore this transition and convergence. The textbook of People's Education Edition has made a useful attempt from mathematics, life to mathematics and thinking, which is worth our in-depth study. I am engaged in primary school mathematics teaching to junior high school mathematics teaching, and have taken some measures for students who have just entered junior high school, and achieved ideal results, which are briefly introduced as follows:
First, stimulate interest in learning and establish a belief in winning.
In the teaching practice of the new curriculum, a truth is drawn: the first class teacher of freshmen must be more carefully prepared. As the saying goes, "If you kiss your teacher, you will believe in it." I started my class like this: after a simple self-introduction, I began to discuss the interest in mathematics, so as to narrow the distance between teachers and students and cultivate the tacit understanding between teaching and learning.
For example, what is the quick calculation of 999998×999992? This aroused students' curiosity, and then led to the "head-to-tail speed compensation algorithm": 83×87, 45×45, 9 1 × 99 ... Through the comparison between students' calculation and teachers' quick calculation, students are very interested. Then let the students go through the process of observation, conjecture, summary and verification, and get the general law; Another example is the binary game of "divination age" displayed by multimedia means. As long as the students say "yes" or "no" to each card, the teacher can finally report the age in the students' minds ... Through such activities, the students can not only sincerely admire the teacher, but also sublimate the teacher-student relationship and lay a solid foundation for further study.
Second, thoroughly understand the differences and change the habit of solving problems.
Mathematics in primary school and mathematics in middle school are not only intrinsically related, but also obviously different. In teaching, we should pay special attention to differences, so that students can avoid detours, and the teaching efficiency can be greatly improved:
1, the expansion of the number field makes the original correct conclusion become a wrong conclusion: for example, "the reciprocal is your own number is _ _ _ _ _ _ _", the answer of primary school students is 1, and the answer of junior high school is not: 1 and-1; Another example is: "The smallest two digits are _ _ _ _ _ _ _". The answer for primary school students is 10, and the answer for junior high school students should be -99. ...
2. Due to different classifications, some numbers are rarely used or even no longer used: for example, "decimal" is completely understood as "fraction" and is replaced by "fractional" or "false fraction". In the second and third grades, the application of classification thought is not uncommon.
3. Problem-solving habits change accordingly: primary school directly solves problems, and junior high school begins: write "solution" in calculation and problem solving; This problem is the most worthy of our first-grade teachers' attention.
4. The conclusion that "the sum of two numbers must be greater than any addend" and "the difference between two non-zero numbers must be less than the minuend" in primary school mathematics is wrong immediately because of the introduction of negative numbers.
In the chapter of rational numbers, based on natural numbers, 0, fractions and decimals learned in primary schools, combined with two examples that primary schools have been exposed to, mainly temperature and altitude, positive numbers and negative numbers are derived, thus expanding the number domain to the scope of rational numbers. In addition, on the basis of describing rational numbers, this chapter compares the four operations learned in primary schools and learns the addition, division and multiplication operations of rational numbers in turn. This arrangement of teaching materials fully embodies the knowledge connection from primary school mathematics to junior high school mathematics, which should undoubtedly be used vigorously as a teacher; Of course, for most students who have just entered junior high school, mathematics knowledge in junior high school is far more abstract than that in primary school. Students often ask teachers whether all the knowledge we learned before is wrong and why it is different from now. How to understand these problems? In this way, only when teachers are familiar with these differences in advance can they be comfortable in teaching.
Third, change thinking habits and cultivate thinking ability.
Mathematics is to cultivate students' thinking ability, and primary school mathematics pays special attention to the cultivation of students' reverse thinking ability. There are many comprehensive formulas for the application of question types when solving problems by comprehensive method. Junior high school mathematics is not like this. It focuses on cultivating students' thinking of transforming the unknown into known equations and solving problems with forward thinking, which is much easier than the thinking mode of primary school. This method is obviously superior to the primary school method, and many problems in primary school mathematics can be solved smoothly by equation method, which is the most important in junior high school algebra teaching. In order to change students' thinking habits, get rid of the shackles of arithmetic thinking and fully understand the superiority of equations. In teaching, we must pay attention to the comparison between the two methods, and compare the advantages and disadvantages of the two ideas through the same example, which is the most convincing.
For example, the sum of the four numbers A, B, C and D is 100, the sum of A plus 4, the difference of B minus 4, the product of C times 4, and the quotient of D divided by 4 is exactly equal, so find these four numbers. It is very complicated to do this problem with elementary school formula, and it is very simple to do it with junior high school equation thought.
4. Infiltrate mathematical ideas and learn the combination of numbers and shapes.
There are many mathematical thinking methods involved in junior high school mathematics, such as the idea of classification, the idea of combining numbers with shapes, and the idea of variables ... all of which require teachers to infiltrate organically in teaching.
The first volume of seventh grade mathematics: when talking about rational numbers, students should be infiltrated with the idea of classification; In the law of rational number addition, it is necessary to classify and discuss various situations of rational number addition. When proving the "theorem of the angle of circle" in ninth grade geometry, we should also carry out classified research and discuss the correctness of the conclusion.
Mathematician Hua said: "the lack of shape is less intuitive, and the lack of shape is difficult to be nuanced;" Numbers and shapes are well combined, and everything is separated. "The first volume of seventh grade mathematics: the number axis is an excellent opportunity to teach students the idea of combining numbers and shapes. It connects rational numbers with points on the number axis, which opens the door for later research.
In mathematics and thinking, we should also infiltrate the idea of incomplete induction.
In a word, I think that if primary school students want to adapt to junior high school mathematics learning quickly, they must attach great importance to the connection teaching between primary school mathematics and junior high school mathematics and put themselves in the perspective of primary school students. Only in this way can they quickly define the requirements of junior high school mathematics, find the connection point between junior high school mathematics and junior high school mathematics, and better grasp junior high school mathematics teaching.