3000 examples in mathematics. Account within 1000. With answers and methodological recommendations. 4th grade

The book has oral addition and subtraction within 1000. By the 4th grade, students learned all methods of addition and subtraction within a dozen, hundreds, thousands. From the third grade, many programs are slowly entering the column. It is much easier to consider in a column than counting even two -digit numbers in the mind. An oral account perfectly trains memory, attention, and logic. Try to introduce students to the column as much as possible as possible, let them decide more examples in the mind-they will better learn to think, reason, build causal relationships.
answers at the end of the book and methodological recommendations on the second and third sides of the cover will help effectively Organize work in the classroom and at home