Mrs. Hoskins’s Math Memo
November 5, 2014
Dear Parents,
I wanted to give you an update on what we have been doing in Math! We have been working
very hard on 2 digit multiplication!!! Over the past several weeks, you have probably seen new
strategies to solve multi-digit problems. These strategies are part of our new common core and
the students are expected to learn these different strategies. We started using 3 different
strategies in Chapter 2 with multiplying a 2 digit number by a one digit number. We used these
same strategies in Chapter 3 to help us learn the process of multiplying a 2 digit number by a 2
digit number. These strategies start with a concrete strategy-area models and partial products, a
representational strategy-partial products with place value, and an abstract strategy of partial
products with regrouping (the traditional method). Your child should be bringing home the Lesson
page from our math book that you can use as a resource to review for our tests and help with
homework. They are told to put it in their math folder inside their binder and review it with their
homework. The Lesson page shows all the steps to follow to complete the strategies. We have
also made an interactive journal that the students use as a resource that helps them take notes and
give examples of the common core targets we are learning. The journal has examples of the
strategies we have learned as well. The students will be allowed to use the journal for a resource
during the test next week. We will continue to review and practice these strategies and then the
students will choose a method that works best for them. They can choose which strategy makes
the most sense to them and what they are most comfortable using to be successful in computation.
We will be having a test over the strategies next week, and students will have to solve a 2 digit
times a 2 digit multiplication problem using all 3 strategies. They will also have to choose a
strategy for real world problem solving. (For example, the students will read a word problem and
pick a strategy to solve the problem).
On Fridays we have been taking timed multiplication tests. Most of the students have passed
their 3’s test and will be testing over 4’s this Friday. Please continue to work on memorization of
basic facts. It is a foundational skill that is necessary to be successful at 2 digit multiplication. We
will start division in Chapter 4 after the test next week. Another reason to memorize those basic
facts!
Below are 3 examples of the strategies we have learned to solve multi-digit multiplication
problems. Thank you for working with your child.
Area models with Partial Products 23x34
20
3
30
4
600
80
90
12
20 x 30 = 600
20 x 4 = 80
3 x 30 = 90
3 x 4 =12
600
80
90
+ 12
782
Mrs. Hoskins’s Math Memo
November 5, 2014
Partial Products using Place Value: 23x34
34
x 23
600
80
90
+ 12
782
20x30=600
20x4=80
3x30=90
3x4=12
Add all of the partial products for your final product.
Partial Products with Regrouping (Traditional method): 23x34
+
+1
34
x 23
102
680
782
34x3:
3x4=12 put the 2 down regroup(carry) the 1 to the tens place
3x3tens=9tens+1=10tens
34x2tens:
2tens x 4=80 Put the 0 in the ones and the 8 in the tens place
2tens x 3 tens=600 Put the 6 in the hundreds place
Add the partial products to get the final product.
Please review these strategies with your child. Talk with him or her on which strategy is the
easiest for them to use to solve multi-digit problems. Thanks!
Mrs. Hoskins