Math Resources

Adding with Base 10 Blocks




Subtracting with Base 10 Blocks






Subtraction by Adding








This page will provide resources for you to use at home. 

Sometimes the information will be posted here or there will be a link to a document.
The document links will direct you to Google Docs. You may download and print these files at your convenience.

If you need clarification about how to use these resources at home,
please contact Ms. Price at her email: rprice@mesquiteisd.org





(click the link above)



Fact Pack

About Learning the Facts - Addition and Subtraction

Learning the basic facts is not an end in itself.  
The goal is to develop fact fluency so that students can solve problems.


Of course, our goal is for all of the students to know all of the facts.  

Students learn the facts in progressive stages.

Stages in Learning the Facts

1.   Concept development:  Through work with manipulative materials and problem solving experiences, students come to understand the meaning of a given number.  For example, to develop the concept of five students find that five can be broken into 1 and 4, 2 and 3, or 5 and 0. 

      Fluency with taking apart numbers to ten and putting them together is an important skill for developing concepts of larger numbers and learning the basic facts.

2.   Strategies:  Students employ strategies to find the answers to basic fact problems.  Although there are 100 basic facts, it is very important for students to understand that the commutative property cuts the job in half.  Turn-around facts, such as 3+7 and 7+3, use the commutative property. 

      Beyond that, knowing that adding or subtracting zero does not change the value of a number, knowing how to quickly count up one or two, learning the doubles and the strategy for near doubles, and knowing how to use the make-a-ten strategy account for all but six of the basic addition facts. 

3.  Learning the facts:  In the process of developing number concepts and fact strategies, students come to learn the basic facts.  That is, they no longer need to think about a fact, they just know it.  For example, students may begin by counting up to find the sum of 8+2, but with experience they no longer need to count up, they automatically think 8+2=10.

4.  Memorizing the facts:  Now is the time to drill for fluency.  Drilling prematurely simply promotes inefficient strategies and possibly even fear of arithmetic.


What about timed practice?  Timed practice to build fluency may be effective with some students who have already learned their basic facts and who enjoy the challenge of the task.  They can learn to recall facts faster. Timed practice tests have negative effects if students are not yet using efficient strategies or if they are fearful of the test.  In that case, timed practice reinforces inefficient practices and develops a poor attitude.  Because of the potential pitfalls, timed practice tests are not recommended. 


Addition Strategies

The materials in this Fact Pack are organized to develop fact strategies commonly employed by students.

·      Facts with Zero:  Any number plus zero is that number.  (This is called the identity property for addition.)

                  Facts with zero:  1+0, 2+0, 3+0 …

·      Count Up:  When one addend is 1 or 2, it is efficient to count up to find the answer.  For example, to add 8+2, the student can count up: 8, 9, 10. 

                                    Count up 1:   3+1, 7+1 …
                                    Count up 2:   4+2, 9+2 …

            (Some students may use count up for facts with an addend of 3.)

·      Doubles:  For some reason, doubles are quickly learned by students.

                  Doubles:  2+2, 3+3, 4+4 …



Source: YouTube; Harry Kindergarten Music


·      Neighbors (near doubles):  When the addends are one apart, the near doubles, or “neighbors” strategy can be used.  For example, to remember 7+8, the student can think 7+7 and 1 more, or 8+8 and 1 less. 

                  Neighbors:  3+4, 4+5, 5+6, 6+7, 7+8, 8+9

·      Fast Nines and Fast Eights:  When one of the addends is close to ten (8 or 9), the other addend can be mentally broken apart to make a ten.  For example, to add 9+7, the student can think 9+1+6; the 7 is broken apart into a 1 -- which goes with the 9 to make 10 -- and 6. 

                                    Fast Nines:            9+3, 9+4, 9+5 …
                                    Fast Eights:            8+3, 8+4, 8+5 …

      This strategy of making a ten can be used with sevens and other addends, too.  To use the strategy efficiently, it is critical that the student be fluent with the facts which add to ten:  1+9, 2+8, 3+7, 4+6, 5+5.

·       The Last Six Facts:  After becoming fluent with the strategies above, there are only six facts left to learn. 

                                    The last six facts:  3+5, 3+6, 3+7, 4+6, 4+7, 5+7

Subtraction Strategies


As with addition, some subtraction facts are more easily learned and then memorized than others.   For example, subtracting 0, 1 or 2 is easy for most students (such as 9-0, 6-1, 7-2).  Also, facts with a difference of 1 or 2 are easy (such as 9-8, 7-5). 

Students who have a thorough knowledge of addition and an understanding of how addition and subtraction are related can learn and remember basic subtraction facts through fact families.
                 
Think addition:  The student uses addition facts to recall subtraction facts.

                                    Think addition:  9 – 4 =?
                                    What do I add to 4 to get 9?  or, 4 plus what equals 9?

This Fact Pack uses fact families and the think addition strategy to help students learn the basic subtraction facts.  Learning and memorizing the subtraction facts requires the same intentional teaching and practice as the addition facts.





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