Advanced Search >

Math Mammoth Add & Subtract 2-B
Quick Preview
/gs_flipbook/flip.php?xml=/demo_xml/2437.xml&w=500&h=324
Full‑size Preview
http://watermark.currclick.com/pdf_previews/2437-sample.pdf

Math Mammoth Add & Subtract 2-B

ADD TO WISHLIST >
Selected Option:
PDF
$5.65
Softcover B&W
$14.24
PDF + Softcover B&W
$19.89
$15.33

Math Mammoth Add & Subtract 2-B is a continuation to the book Math Mammoth Add & Subtract 2-A. The goal of this book is to study addition and subtraction within 0-100, both mentally and in columns, especially concentrating on regrouping in addition (carrying) and in subtraction (borrowing).

The PDF version of this book is enabled for annotation. This means that if you prefer, your student can fill it in on the computer, using the typewriter and drawing tools in Adobe Reader version 9 or greater.

Mental math

Mental math is important because it builds number sense. This book includes many lessons that practice mental math. For example, the child practices adding and subtracting two-digit numbers when one of the numbers is a whole ten (problems such as 30 + 14, or 66 − 20).

Also studied are problems such as 36 + 8 or 45 + 9. These problems use the idea of going over ten as in problems 6 + 8 and 5 + 9. The child knows that 6 + 8 fills the first ten and is four more than the ten. He/she will learn to use that fact when adding 36 + 8. The sum 36 + 8 fills the next whole ten (40), and is four more than that, or 44.

Regrouping in tens

Simultaneously with this, the child learns adding two-digit numbers in columns, and regrouping with tens, or "carrying," which is illustrated and explained in detail with the help of visual models. These visual models take the place of base-ten blocks or other manipulatives. You are welcome to use manipulatives to get the idea across, if you prefer. The main concept to understand is that 10 ones are regrouped to form a new ten, and this new ten is written using a little "1" in the tens column.

Regrouping in subtraction

The next lessons teach subtracting in columns. First we only deal with the easy problems where you don't need to regroup (borrow). Then the following lessons practice in detail the process of regrouping or borrowing. You can use either term with your child, or even choose not to use either if you feel it is confusing. You can alternatively use the phrase "breaking a ten into ten ones."

First, the lesson Regrouping practices breaking down a ten into ten ones because we cannot subtract from the ones. It is crucial that the child understands what happens here. Otherwise, he/she might end up only memorizing the procedure, and will probably at some point misremember how it was done. That is why this lesson deals with the regrouping process in detail with plenty of visual exercises.

If you notice that the child does not understand the concept of regrouping, he/she may need more practice with concrete manipulatives or visual exercises before proceeding.

More mental math

After learning regrouping, we practice mental subtraction in three separate lessons. One of them expounds on several methods for mental subtracting. Another is about Euclid's game—a fun game that also practices subtraction of two-digit numbers.

 
 Customers who bought this title also purchased
Reviews (3)
Discussions (0)
Reviews
-
March 28th, 2009
I think this program offers a very good variety of exercises to help the child think mathematically. The mental math is very good for helping the child to really understand the concept. The author does a good job of explaining and illustrating each con [...]
-
March 5th, 2009
My son was struggling with learning to borrow in subtraction problems, so we purchased this little book. We were using a different curriculum and he liked this for a change of pace. The pages have some color in them which he liked. Some pages had A LOT [...]
-
May 8th, 2007
I'm not loving this book. The font is way too small. The illustrations of place value materials is tiny. There is absolutely no teacher tips on how to get the lesson across to your student(s). Some of it is self-explanatory, but some of it made me look [...]
Browse Categories
 Follow Your Favorites!
NotificationsSign in to get custom notifications of new products!
Product Information
Gold seller
Appropriate Age(s)
Author(s)
Appropriate Age(s)
Pages
95
File Size:
4.01 MB
Format
Original electronic
Scanned image
These products were created by scanning an original printed edition. Most older books are in scanned image format because original digital layout files never existed or were no longer available from the publisher.

For PDF download editions, each page has been run through Optical Character Recognition (OCR) software to attempt to decipher the printed text. The result of this OCR process is placed invisibly behind the picture of each scanned page, to allow for text searching. However, any text in a given book set on a graphical background or in handwritten fonts would most likely not be picked up by the OCR software, and is therefore not searchable. Also, a few larger books may be resampled to fit into the system, and may not have this searchable text background.

For printed books, we have performed high-resolution scans of an original hardcopy of the book. We essentially digitally re-master the book. Unfortunately, the resulting quality of these books is not as high. It's the problem of making a copy of a copy. The text is fine for reading, but illustration work starts to run dark, pixellating and/or losing shades of grey. Moiré patterns may develop in photos. We mark clearly which print titles come from scanned image books so that you can make an informed purchase decision about the quality of what you will receive.
Original electronic format
These ebooks were created from the original electronic layout files, and therefore are fully text searchable. Also, their file size tends to be smaller than scanned image books. Most newer books are in the original electronic format. Both download and print editions of such books should be high quality.
File Last Updated:
April 18, 2018
This title was added to our catalog on January 01, 2005.