Knowledge points of "addition and subtraction within 100" in senior one mathematics.
1. Ten digits are added and subtracted, and one digit is added and subtracted.
1, carry-free addition 20+30=5067+2=6968+30=98.
2. Subtraction without abdication 80-50=3069-2=6798-30=68
Second, carry addition (add up to ten)
1, make up ten songs: one for nine, two for eight, three for seven, four for six and five for ten. (Note: Two figures rounded to ten are complementary.)
2.20 Carry-in addition: decimal method: 8+72= 15, ten digits plus 1, one digit minus the complement (2+8= 10, 2 is the complement of 8).
3. 100 plus 362+8=44 decimal extraction method: the digits are connected by arcs, and the digits are added to 1 and subtracted. (The method is the same as within 20)
Third, abdication subtraction.
1, abdication less than 20: ten-break method: 16 1-9=7 digits' complement.
2. If abdication is less than 100: 36 1-9=27, refining method: units are connected by arcs, ten units are subtracted by 1, and units are supplemented.
The knowledge point of "understanding numbers within 100" in senior one mathematics.
1, from the right, the first digit is one, the second digit is ten, and the third digit is one hundred.
Reading and writing methods: both reading and writing should start from the high position.
2. Singular number: a natural number with the unit of 1, 3,5,7,9.
3. Even numbers: natural numbers with units of 0, 2, 4, 6 and 8 (except 0).
4. Integer: a natural number with the unit of 0 (except 0).
Five tens and five ones make fifty-five. (Five decimal places means five tens, and five decimal places means five ones. )
Reading: 55 (writing Chinese characters) Writing: 55 (writing mathematical characters)
6, 10 one is ten, 10 ten is one hundred. (One, ten and hundred are counting units. Write Chinese characters)
Composition of numbers: (Pay attention to different ways of asking questions)
Example: 68 consists of 6 tens and 8 ones; 68 consists of 8 1 and 6 10.
There are (6) tens and (8) ones, and (68) ones.
The decimal digit is 6, which means 6 tens (writing Chinese characters), and the unit digit is 8, which means 8 ones (writing Chinese characters).
7. The method of comparing the size of two digits: look at the ten digits first, and the bigger the number, the bigger it will be. If the ten digits are the same, if you look at one digit, it will be bigger. (The opening faces a large number and the tip faces a decimal number. )
8. When the difference between the two quantities is large, it can be described as "much more, much less"; When there is little difference between the two quantities, it can be described as "more, less".
9. The smallest three digits are100; The two digits of are 99; The smallest two digits are10; One digit of is 9; The smallest number is 1.
Mathematics learning methods and skills
Create a good atmosphere in the lecture hall
Modern educational theory holds that a good lecture hall atmosphere can be a silent medium to convey common sense, the key to enlighten wisdom and the potential power to cultivate morality. Every teacher knows that the atmosphere in the lecture hall greatly affects the students' learning automaticity. In education, teachers plan students' favorite and emotional learning activities, stimulate students' love for learning, and let students learn mathematics happily; Teachers provide students with rich opportunities to participate in mathematical activities, guide students to acquire mathematical common sense, technology and mathematical thinking methods through independent research and cooperative exchange, and let students experience a vivid, automatic research and distinctive invention process. All this needs an excellent lecture hall atmosphere to support.
Teachers should create a democratic and harmonious learning atmosphere for students. The real democracy and harmony in the lecture hall stems from a teacher-student relationship. The educational process is a two-way process of information exchange between teachers and students, and it is also a process of emotional exchange between teachers and students. Through their own educational activities, teachers moisten students' hearts with love, stimulate students' enthusiasm for learning mathematics, and make them actively participate in learning activities automatically. Take the lesson "Knowing 0 and Related Addition and Subtraction" as an example. In the activity of writing 0, the teacher used these words "Do you want to write 0?" Ok, hold out your little hand and look at the blank screen book. Draw a line of 0 in the Japanese word box. What do you think should be paid attention to when writing 0? "What do you want to say to the children in our class?" "The teacher thinks that your 0 must be beautifully written, so start writing a few 0 s in the Japanese word box below! "Arrange students to carry out activities such as book blank, drawing, summary writing and independent writing.
The teacher's words are permeated with understanding, respect and trust for students, and they are deeply concerned about students, so that students can get the method of writing 0 happily and automatically. In the process of learning common sense, when students make mistakes, don't criticize them, but give them another chance. For example, ask students to say, "How many peaches are marked on the plate/kloc-0?" At this time, the reply "Little monkey ate 1 peach, marked 1" appeared. The teacher didn't worry, then asked, "How many peaches are there in that plate?" The child immediately said, "It's marked 1." How many frogs are there on two lotus leaves? When one student says 4-0, other students are eager to express their own equation 4+0 or 0+4.
At this time, the teacher gave the students a chance to correct themselves and asked them to say it again on the grounds that "the teacher didn't hear clearly". Wonderful has won students the opportunity to understand success. "Give students another chance" makes them feel warm and encouraged, keep their love for learning, and keep their enthusiasm for learning and learning common sense. In a democratic, relaxed and harmonious educational atmosphere, students feel comfortable, have vivid thoughts, dare to think, dare to feel and dare to speak, and their learning potential and automaticity are fully brought into play.
Articles related to mathematical knowledge points in the second volume of Senior One;
★ Senior 1 Mathematics Book II Knowledge Point Part Edition
★ Summary of first-grade mathematics knowledge points
★ Department Editor 100 Special Exercise on Math Application Problems in Grade One of Primary School.
★ First-year Chinese knowledge points compiled by the Ministry (complete works of Volume I and Volume II)
★ Guidance of mathematics learning methods in the first grade of primary school
★ Guidance on learning methods for the first grade.
★ Summary of knowledge points in the first grade mathematics department edition
★ Editor of Mathematics Knowledge Point Department of Senior One.
★ English exercises in the second volume of the first grade of primary school
★ Learning skills of primary school students