The reason why multiplication formula is unfamiliar
The reason why multiplication formula is unfamiliar is that multiplication formula has a long history in ancient China. Therefore, as China people, we should remember the multiplication formula. There is no harm, but it is difficult for many children to master it now. Today, I will summarize the reasons why multiplication formulas are unfamiliar.
The reason why multiplication formula is unfamiliar is 1. We started the whole process of reciting the formula table.
The formula table we usually see is like this.
Write down this formula, for a child, it is almost necessary to try to suck milk.
We usually think that we can only learn by rote. Let me talk about some experiences I recited with my children these two days.
Prompt 1: The dimension is reduced and the quantity is greatly improved.
I made a new table with Excel, and removed two parts that are diagonally symmetrical, so the total number will be less than half. At present, there are only 45 formulas to memorize.
Tip 2: Exclusion method, quickly skip the simple part.
The light green part below is like playing for children. Easy to understand, so the number can be reduced by 9, and the formula that needs to be memorized becomes 45-9=36.
Tip 3: delimit the range of data products and limit it to 20.
In order to concentrate more, I directly removed the formula of 1 sequence. The light green part below can be recited by children. Why did you choose this? One of the most important reasons is that for children, we only have a certain feeling about numbers within 20 at present, so our product range should be within 20 as far as possible. For adults, it is still difficult to process data from 6 to 9, so we can put it aside for the time being.
This recitation sequence starts from the number 2 sequence, starts from 2*2, continues to 2*9, and then starts from the six formulas of the horizontal line.
Tip 4: Cultivate a sense of data and define the scope.
Next comes the dark part. We can make children recite numbers from 2 * 2 to 9 * 9. There are some tricks at this stage, such as 8*8=64. I will say "Dad is 64 years old", and the children will remember it soon.
It will take about a day to learn the above.
Tip # 5: Reciting the formula of 9 series can be tricky.
The next part of learning is a bit difficult. I said, it's the hardest to learn from children first. In the order of horizontal 9, start from 3*9 to 8*9. There are some detours in this process. Originally, it was carried by children. As a result, children read it many times, remembering the front and forgetting the back. The effect is average.
I observed that the formula of 9 has a trick, such as 3*9, and its result is one bit smaller than the 3 of 10 digit. You can shout out "20" without hesitation, and then your numbers add up to 10, which means 10-3=7, which means the unit is 7, so the answer is "3927". A similar model can also be used for children with larger numbers in the back.
Tip 6: Split and gradually expand the data range.
Finally, there is 12 left, and I plan to break through one by one. For example, I learn the yellow part first, which is in my early twenties. For 5 * 6, 5 * 7 and 5 * 8, children can have a certain understanding of the increment of 5.
Tip 7: Formula cards, numbers and Chinese formulas echo.
During the whole learning process, I found a formula card with digital products on the front and Chinese formulas on the back.
In the process of learning, the remaining formula cards are also less, and there is also a sense of accomplishment for children.
Tip 8: Test randomly like playing cards.
Of course, I also participated in the whole process, and I will make the formula cards that children have mastered into card models, so that children can draw cards and answer them themselves, and the effect is not bad.
The multiplication formula is unfamiliar. Reason 2 There is a knack for memorizing multiplication formulas! Let children say goodbye to rote learning methods, and the more they learn, the easier it is.
There are three reasons why children are not encouraged to memorize multiplication formulas:
First, memorizing formulas is boring, and it is not easy for children to improve their interest.
For many primary school students, interest is the motivation of learning.
Some children are not good at math because they think math knowledge is boring and difficult to understand. If even the multiplication formula becomes "cramming", it will only reduce children's goodwill towards math again.
Second, rote memorization is not strong, and children forget it and forget to recite it again, which is easy to get confused.
"Ebbinghaus Forgetting Curve" As we all know, if children have to memorize, they can only repeat it and strengthen their memory. However, as Deng Chao's father in Looking Up said: Practice over and over again, remember over and over again, just like steaming steamed bread over and over again, will it taste good in the end?
Children don't like rote learning, and they hate it again and again. This method will not only make mathematics "very bad", but also may not be effective. Children may be more confused when they recite, more confused when they learn, and more likely to make mistakes when they do it.
Third, the rigid learning style will only make it harder for children to learn.
Why do many children's math scores plummet in the third and fourth grades? It must be related to learning style.
The knowledge of the first and second grades is relatively simple, even if the children learn more rigidly, it may not be reflected in their grades. But in fact, since I was exposed to multiplication in the second grade, the complexity of mathematical calculation has risen sharply.
From the third and fourth grades, children will gradually learn to multiply two digits by one digit, two digits by two digits, and divide by one digit and two digits. If you recite the multiplication formula, the foundation is not firm and the method is not mastered properly, it will greatly affect the calculation speed and correct rate.
These may not be obvious at the beginning of learning the formula, but the later, the bigger the gap will be.
In addition, since the third and fourth grades, the complexity of mathematical application problems has also increased. In the first and second grades, the questions are simple and there are many suggestive words. It is impossible to see whether the child really knows or is "blind".
In the third and fourth grades, the application problem will examine the application of four operations and elementary arithmetic. If children can understand the deep logic behind multiplication and multiplication formula and understand the corresponding mathematical laws, it will be of great help to understand application problems and even develop mathematical thinking.
On the other hand, if he still learns by rote, even if he can memorize the multiplication formula, he may not be able to do some flexible calculations and application problems correctly.
In a word, calculation is the focus of mathematics learning and the spark of mathematical thinking, and multiplication formula is a leap in the history of calculation and the soul of calculation.
Changing the learning method of rote multiplication formula can refresh children's cognition of mathematics, change the way children learn mathematics, and let children find that mathematics can also be very interesting and fun.
What are some ways to say goodbye to rote learning and let children easily master the multiplication formula?
When learning multiplication formula, two ideas can be infiltrated:
Idea 1: Multiplication is a simple calculation of addition.
I am in "Children are always careless when doing calculation problems?" As mentioned in the article "There are better methods besides repeated exercises and exams", the multiplication table in our mathematics textbook is not very instructive and is not helpful to children's memory and study.
Therefore, it is recommended that every parent let their children make a multiplication table as shown above. In the process of filling in numbers, children can actually find many rules.
As can be seen from the figure, it is not difficult to memorize the multiplication formula of 1-5. For example, if you multiply 1, 2, 3, 4, and 5 by 2 respectively, the results will all add 2 in turn. Similarly, if you multiply 1-9 by 5 in turn, the result will be added by 5 in turn.
It can be seen that the multiplication formula of 1-5 is actually constantly adding, and children will find this rule whether they look horizontally or vertically in the table.
On this basis, by memorizing multiplication formula, we can find the relationship between multiplication and addition, and the relationship between factor and product, which is of great help to learning comprehensive calculation, solving application problems and even discovering the law of sequence.
Thought 2: The laws of mathematics are everywhere, and the beauty of mathematics is everywhere.
Using this form to learn the multiplication formula, we will find many interesting laws:
1. Whether viewed vertically, horizontally or obliquely, the changes of numbers have their own laws. See my article for details.
Children are always careless in calculating problems? There is a better way than practicing exams repeatedly.
2. With regard to the multiplication formula of 9, it can be seen that any number multiplied by 9 adds up to 9.
The longer children look at this watch, the more they can discover the fun and symmetrical beauty of mathematics:
1. If the diagonal line from the upper left to the lower right is the axis of symmetry, we will find that the numbers on both sides of it have a specific regular change, and they are symmetrical (equal).
2. Regarding the multiplication formula of 9, there is also a symmetrical beauty of "pairwise echo":
2×9= 18、9×9=8 1;
3×9=27、8×9=72;
4×9=36、7×9=63;
5×9=45、6×9=54。
More importantly, this process of discovery and exploration does not require too much guidance from parents, but only encourages him to see more and think more. When he gropes for the corresponding laws step by step, he will get incomparable joy and sense of accomplishment.
On the basis of this active exploration, memorizing the formula of multiplication will leave a deeper impression and a more lasting effect.
The multiplication formula is unfamiliar. Reason 3 The mathematical multiplication formula prompts the children to recite the formula.
The multiplication formula table can be divided into several parts and can be recited vertically: only one part is recited at a time.
For the first time, it is easy to recite from "one gets one" to "one gets nine". After reciting this, recite the second column: from "two get four" to "two get eight".
After reciting the second column, combine the first column and the second column to recite the memory. By analogy, if the child has been too difficult to recite, he can only recite two or three columns all day according to his own situation, but he is required to recite them. In the process of memorizing, any child who can't remember will read a lot, read more than ten or twenty times, and then sum up with the previous summary after memorizing. In this way, the child will recite it in almost a week.
You can also cross your back: it is also divided into several parts. Recite two lines for the first time: from "one to one" to "two to four". This is easy to recite. After reciting, recite the third line for the second time: from "one to three" to "three to nine". After reciting, I will summarize it with the first time, and then recite it. In this order, I will recite two lines all day, almost a week.