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What’s My Noun? Adjective/Noun next Taking the Fear out of Math © Math As A Second Language All Rights Reserved Quantities vs. Numbers.

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Presentation on theme: "What’s My Noun? Adjective/Noun next Taking the Fear out of Math © Math As A Second Language All Rights Reserved Quantities vs. Numbers."— Presentation transcript:

1 What’s My Noun? Adjective/Noun next Taking the Fear out of Math © Math As A Second Language All Rights Reserved Quantities vs. Numbers

2 In our previous lesson, we emphasized the importance of this fact… next Even though addition tables tell us that 3 + 2 = 5, the fact is that 3 dimes plus 2 nickels is neither 5 dimes nor 5 nickels. © Math As A Second Language All Rights Reserved When we add two quantities the correct result is the sum of the adjectives (numbers) only if the nouns (the units) are the same.

3 next To find the amount of money, we converted both quantities to a common unit and then added. 3 dimes + 2 nickels = 30 cents + 40 cents next 10 cents = next © Math As A Second Language All Rights Reserved

4 next For example, the value of 2 nickels is 1 dime. Hence, we may restate the problem in the form… 3 dimes + 2 nickels = 3 dimes + 1 dime = 4 dimes 1 Note… There may be more than one common unit. note 1 In our adjective/noun theme we do not distinguish between singular and plural. The fact is that while “dime” and “dimes” are different nouns they represent the same unit. next © Math As A Second Language All Rights Reserved

5 next And even though 40, 4, and 8 are different adjectives (numbers), 40 cents, 4 dimes and 8 nickels all describe the same quantity. 3 dimes + 2 nickels = 6 nickels + 2 nickels = 8 nickels We could also have used nickels as the common unit, in which case we could have replaced 3 dimes by 6 nickels to obtain… © Math As A Second Language All Rights Reserved

6 A Preview of Coming Attractions At first glance, our emphasis on the adjective/noun theme might seem like little more than just a novelty, but as we will see throughout the study of arithmetic, this theme can greatly improve students’ ability to internalize all of arithmetic. next © Math As A Second Language All Rights Reserved

7 We will discuss this in greater detail as the course progresses, but for now let’s focus on just one aspect of how the adjective/noun theme simplifies arithmetic algorithms that often befuddle students. next © Math As A Second Language All Rights Reserved

8 next Too often the “numerator” is introduced as a synonym for “top” and “denominator” as a synonym for “bottom”. Note… On the Terms Numerator and Denominator © Math As A Second Language All Rights Reserved This obscures the fact that the numerator is the adjective and the denominator is the noun and leaves many students confused when they are asked to add fractions. top bottom numerator denominator adjective noun ==

9 next When adding two fractions, students feel it is more natural to add the two numerators to obtain the numerator of the sum and to add the two denominators to obtain the denominator of the sum. For example, they would prefer that adding 1 / 2 + 1 / 2 would mean to do the following… © Math As A Second Language All Rights Reserved 2 4 1212 1212 += 1 + 1 2 + 2 = …which is a result that they will most likely recognize as being incorrect”.

10 next However, once the proper definitions are given for numerator and denominator, these students will quickly realize that this is not the correct way to add fractions. Namely, when they are called upon to compute a sum such as 6 nickels + 2 nickels, they would add the two adjectives (6 + 2) but then keep the common denomination (nickels). Even though it is true that a nickel and a nickel is a dime, in no way would they have felt that the answer was 8 dimes. © Math As A Second Language All Rights Reserved

11 Guess My Noun next Guess My Noun is a fun way to reinforce the notion of the adjective/noun theme and how 3 + 2 = 40 can be a true statement. For example, if there are certain facts you want the students to know (such as the fact that 7 days = 1 week) you might ask them to supply the nouns for… 7 ______ = 1 ______. © Math As A Second Language All Rights Reserved

12 next If we want to emphasize that there are 12 months in a year, fill in the blanks for the missing nouns in… 12 ________ = 1 ______. Notice that there can be more than one correct answer. 12 inches = 1 foot monthsyear 12 eggs = 1 dozen eggs © Math As A Second Language All Rights Reserved

13 next You might wonder why 12 was chosen rather than 10 for the number of inches in a foot. Such a question can lead to the “discovery” of whole number fractional parts. For example, since “teen” means plus ten, one might naturally assume that the first teen should come after ten. That is, the number we call eleven should have been called “oneteen”. © Math As A Second Language All Rights Reserved So why does the first teen come after twelve not ten?

14 next As surprising as it might seem, the concept of ten was not considered to be important until the advent of place value. Until that time, people preferred to avoid the need for using fractions whenever possible. Therefore, since 12 had more proper divisors than 10, it meant that by having a foot consist of 12 inches, more fractional parts of a foot would be a whole number than if there had been 10 inches in a foot. © Math As A Second Language All Rights Reserved

15 next Aside from the “folk lore” values of these examples, it might be reassuring to students for them to know that hundreds of years ago people were already learning how to invent nouns that would minimize the need for using fractions. © Math As A Second Language All Rights Reserved

16 next You may prefer additional examples, and you should feel free to create problems of your own choosing. Students also may want to create their own problems to challenge their classmates. © Math As A Second Language All Rights Reserved Depending on the grade level you can ask more difficult questions by having the students add different quantities such as… 2 _____ + 12 ______ = 1 ______feetinchesyard next

17 Examples such as 3 + 2 = 40 are too sophisticated for children in grades K – 2. Instead, colored rods of different lengths may help to reinforce the adjective/noun theme at the lower grade levels. © Math As A Second Language All Rights Reserved

18 next From a different perspective, you could see that… 1 blue rod = 12 red rods 1 blue rod = 6 green rods next © Math As A Second Language All Rights Reserved

19 next 1 blue rod = 4 yellow rods 1 blue rod = 3 white rods next 1 blue rod = 2 purple rods © Math As A Second Language All Rights Reserved

20 next Therefore… 2=1 3=1 4=1 6= 1 © Math As A Second Language All Rights Reserved

21 next 12 1 2 3 4 66 44 333 22222 11111111111 In summary… next © Math As A Second Language All Rights Reserved

22 next You could give your students examples in adding quantities such as… 1 white rod1 purple rod+ 1 green rod = next In later grades, the above equality could become a visual model for showing that 1 / 3 + 1 / 6 = 1 / 2 (that is, 1 third + 1 sixth = 1 half). © Math As A Second Language All Rights Reserved

23 next Another example might be… 5 red rods3 yellow rods+ 1 white rod = next (that is, 5 twelfths + 1 third = 3 fourths) © Math As A Second Language All Rights Reserved

24 next If time is limited, assign them as homework under the heading of such phrases as “Fun With Math” and make sure that students know that it is just for fun and that they will not be graded. Rather they should be encouraged to work on the problems and share their results with the class (as time permits). Guess My Noun © Math As A Second Language All Rights Reserved

25 Guess My Noun next We know that you are under pressure to cover a certain amount of prescribed content, and that as a result you may feel that there is no time for such “games” in your class. However, our approach to helping students to better internalize mathematics hinges on their thorough grasp of adding quantities using the adjective/noun theme, and the previous examples are fun ways in which to learn. © Math As A Second Language All Rights Reserved


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