3000 examples in mathematics. We count and explain. Addition and subtraction. Grade 3

The manual contains examples on the basic topics of mathematics for the 3rd grade “Addition and subtraction within 100” and “Addition and subtraction within 1000”, which will help to work out to automatism all types of account techniques: without transition through the category of type 45+12, 45–45– 12, with the transition through the category of type 67+5, 34–5 and type 67+15, 73–15, numbering calculations of the type 239+1, 200–1, calculations with round numbers without crossing the category of type 260+30, 260– 30.
For each account receipt, algorithms are given, knowing which, the child will calculate correctly and quickly. It is very important to bring the skill of using the account algorithm to automatism. It is most effective for this to use the commented score.
First, the teacher explains how to consider - clearly pronounces and repeats the account algorithm. Then the children take turns saying an algorithm when solving examples in columns. The child should reason as it is written in the algorithm. For any difficulty, he needs to help, prompt. If the child learns to speak well, he will learn to quickly count, and this is the key to success in high school when you have to perform complex calculations.
Manual can be used in school lessons and for independent classes at home