1. The line segment is straight and the two ends are round. You must draw it with a ruler and write down the length.
2. Operate sequence songs
Playing bamboo boards is ringing all over the sky. Listen to me, students Don't talk about other watches today, let's talk about the operation. Clear order is the key to calculating mixed questions. The operation at the same level is the best, and it is calculated from left to right in turn. Two levels of operations appear, first multiply and divide and then add and subtract. What should I do if I encounter parentheses? Count the parentheses first, then the parentheses. The order must not be out of order. Check every step, and I will be happy again.
3. Know the clock
The fastest runner is the second hand, tall and in good shape;
The slowest runner is the hour hand, short and fat. Height and height are not minute hands, so running at a constant speed is very effective.
When you know the hours and minutes, the hour hand passes through the numbers, which means how many hours and how many minutes. Please look at the minute hand carefully.
4. I am 1 cm.
1 cm, very naughty, look carefully before you look. Nail cover 1 cm, stretch out your finger and compare it. It's about my length, about one centimeter. 100 I'm 1 m, I'm a little brother. Don't use me when the object is long, or you'll be exhausted.
5. The usage of greater than sign and less than sign is greater than sign and less than sign. Smile at the big numbers.
6, pen addition pen addition should pay attention, the same numbers should be aligned; Start with a single digit. If one digit is full of 10, go up to ten digits.
7, abdication subtraction abdication subtraction should be kept in mind, starting from the unit; Who is not enough to retire, don't forget to add ten to the standard; If the interval is 1, it is best to remember that 0 becomes 10.
8, rhyme into the law.
A frog has a mouth, two eyes and four legs. Two frogs have two mouths, four eyes and eight legs. Three frogs have three mouths, six eyes and twelve legs. Four frogs with four mouths jumped into the water.
9. Phrases of elementary arithmetic: Clear order is the key to the calculation of mixed test questions. ? +? , the best calculation, from left to right; ? +? ,,,, all appear, multiply first and then divide and then add and subtract; Encounter? ()? What should I do? Parentheses count first. Check every step, and be happy when you are right.
/kloc-carry addition within 0/0 and 20
Look at a large number, divide it into decimals, round it to ten, and add a fraction. (master? Make up ten Advocate? Recursive method. )
1 1 and abdication subtraction within 20.
Less than 20 abdicates, and the oral calculation method is simple. Ten people return one, one person makes up, and the writing is accurate and fast.
Additive meaning, vertical calculation
12, when two numbers are added, the result of the addition is called sum. Don't forget the numbers on the right, one for every ten.
13, the significance of vertical calculation subtraction
Subtraction is used from big to small, and the result of subtraction is called difference. Digital alignment starts from the right, and when it is not enough, take the front position.
Phase difference relation
14, how much more, how much less, is a big reduction. 2. The proportion of known conditions is more, less than before. 3. The proportion of known conditions is small, and the proportion is reduced first and then increased.
15, solving the application problem of children's songs
16, read the topic several times to find the key points; Look at what you want first, and then find conditions; Reasonable calculation formula, careful calculation; Ask for more answers to a question, and the unit will not forget it; Check the results and finally write the answer.
17, small angle, really simple, (one) vertex, (two) edges.
18, angle size, see (fork), the bigger the fork, the bigger the angle. It doesn't matter if the side length becomes shorter.
19, draw an angle
20. Draw a circular point (representing the vertex of the angle) first, and then draw two lines (representing the edge of the angle) from this point in different directions with a ruler to draw an angle.
2 1. Phrase description: When drawing a corner, pay attention to drawing (vertex) first and then (edge).