Math Mammoth Add and Subtract 2-C focuses on regrouping in addition
(a.k.a. carrying) and in subtraction (a.k.a. borrowing), on a second grade level.
The book assumes the student has already learned to add two-digit
numbers with regrouping. In this book, students will learn 3-digit addition
with regrouping, and both 2- and 3-digit subtraction with regrouping, with
one exception: this book does not cover regrouping over zero tens in
subtraction, as that topic is left for 3rd grade level in the Math Mammoth
curriculum.
In the first lesson, the student adds three-digit numbers with a regrouping in
tens, but there is no regrouping in hundreds.
In the next lesson, students regroup 10 tens as a hundred (or carry to the
hundreds).
Then we study regrouping twice in addition: 10 ones form a new ten, and
then 10 tens form a new hundred.
Then, they learn the abstract process, adding the numbers in columns.
Next, we study regrouping in subtraction, starting with two-digit numbers.
Next, there is a lesson on word problems that include the thought of ÒmoreÓ
or ÒfewerÓ, and also several techniques or ÒtricksÓ for mental subtraction.
The word problem sets in the book typically include both addition
and subtraction problems.
After this, it is time to study regrouping in subtraction with three-digit
numbers.
Lastly, students work with bar graphs and play EuclidÕs game, which is meant
as a fun, supplemental lesson., math, addition, subtraction, 3rd grade, Maria Miller| | 61PAGES