1. Teaching measurement MATH 124

2. Key ideas in teaching measurement Making comparisons between what is being measured and some suitable standard of measure (Burns) It is key that children get ample practice with measurement It is also key to understand that measurements are never exact, and that children need to learn what it means to be “close enough,” and to make estimates

3. What should be taught in the elementary curriculum? 1. Making comparisons between objects by matching, without use of measuring tools. For example, students compare who is taller or who has a longer foot. 2. Comparing objects with nonstandard units. For example, they can measure height using parts of the body, straws, books, etc. 3. Comparing objects with standard units, both metric and standard. 4. Choosing suitable units for specific measurements

4. The four stages described above should be used in teaching length, time, weight/mass, volume/capacity, temperature and area Before third grade, students should use direct comparisons and nonstandard units to make comparisons; after third grade, they can move into standard units of measure

5. Example: body ratios Estimate how many times a piece of string equal to a student’s height would wrap around his/her head as a headband, then measure (the ratio should be close to 1:3) Estimate, then find the ratio between the length of a student’s foot length and height (should be close to 1:6) “Are you a square or a rectangle?” “Fit a drawing of yourself on a 5x8 index card” Note: caution should be used when working with student body measurements

6. Standard units 1.We usually use standard units when giving values of quantities. For example, the English system includes the ounce, pound, ton, inch, yard, mile, etc., and the metric system uses the gram, kilogram, metric ton, centimeter, meter, kilometer, etc. Why are standard units used? 2.Why are there so many different units for the same characteristic, even within one system of measurement? For example, the English system has the units ounce, pound, and ton for measuring weight.

7. Metric units Why has the U. S. public resisted adopting wholeheartedly the metric system?

8. Introducing the metric system Cuisenaire rods ▫ Which things are as long as the white rod? ▫ Which things are as long as an orange rod? ▫ Which things are as long as 10 orange rods? Metric body measurements: what is 1cm long; 1 dm long; 1 m long? Students make their own metric ruler Practice measuring using metric units: sample activitysample activity

9. Metric units Look at page 519

10. Common Core: Kindergarten CCSS.Math.Content.K.MD.A.1 Describe measurable attributes of objects, such as length or weight. Describe several measurable attributes of a single object.CCSS.Math.Content.K.MD.A.1 CCSS.Math.Content.K.MD.A.2 Directly compare two objects with a measurable attribute in common, to see which object has "more of"/"less of" the attribute, and describe the difference. For example, directly compare the heights of two children and describe one child as taller/shorter.CCSS.Math.Content.K.MD.A.2

11. Common Core: 1 st grade CCSS.Math.Content.1.MD.A.1 Order three objects by length; compare the lengths of two objects indirectly by using a third object.CCSS.Math.Content.1.MD.A.1 CCSS.Math.Content.1.MD.A.2 Express the length of an object as a whole number of length units, by laying multiple copies of a shorter object (the length unit) end to end; understand that the length measurement of an object is the number of same-size length units that span it with no gaps or overlaps. Limit to contexts where the object being measured is spanned by a whole number of length units with no gaps or overlaps.CCSS.Math.Content.1.MD.A.2 CCSS.Math.Content.1.MD.B.3 Tell and write time in hours and half-hours using analog and digital clocks.CCSS.Math.Content.1.MD.B.3

12. Common Core: 2 nd grade CCSS.Math.Content.2.MD.A.1 Measure the length of an object by selecting and using appropriate tools such as rulers, yardsticks, meter sticks, and measuring tapes.CCSS.Math.Content.2.MD.A.1 CCSS.Math.Content.2.MD.A.2 Measure the length of an object twice, using length units of different lengths for the two measurements; describe how the two measurements relate to the size of the unit chosen.CCSS.Math.Content.2.MD.A.2 CCSS.Math.Content.2.MD.A.3 Estimate lengths using units of inches, feet, centimeters, and meters.CCSS.Math.Content.2.MD.A.3 CCSS.Math.Content.2.MD.A.4 Measure to determine how much longer one object is than another, expressing the length difference in terms of a standard length unit.CCSS.Math.Content.2.MD.A.4 CCSS.Math.Content.2.MD.B.5 Use addition and subtraction within 100 to solve word problems involving lengths that are given in the same units, e.g., by using drawings (such as drawings of rulers) and equations with a symbol for the unknown number to represent the problem.CCSS.Math.Content.2.MD.B.5 CCSS.Math.Content.2.MD.B.6 Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2,..., and represent whole-number sums and differences within 100 on a number line diagram.CCSS.Math.Content.2.MD.B.6

13. CCSS.Math.Content.2.MD.C.7 Tell and write time from analog and digital clocks to the nearest five minutes, using a.m. and p.m.CCSS.Math.Content.2.MD.C.7 CCSS.Math.Content.2.MD.C.8 Solve word problems involving dollar bills, quarters, dimes, nickels, and pennies, using $ and ¢ symbols appropriately. Example: If you have 2 dimes and 3 pennies, how many cents do you have?CCSS.Math.Content.2.MD.C.8

14. Common Core: 3 rd grade CCSS.Math.Content.3.MD.A.1 Tell and write time to the nearest minute and measure time intervals in minutes. Solve word problems involving addition and subtraction of time intervals in minutes, e.g., by representing the problem on a number line diagram.CCSS.Math.Content.3.MD.A.1 CCSS.Math.Content.3.MD.A.2 Measure and estimate liquid volumes and masses of objects using standard units of grams (g), kilograms (kg), and liters (l). 1 Add, subtract, multiply, or divide to solve one-step word problems involving masses or volumes that are given in the same units, e.g., by using drawings (such as a beaker with a measurement scale) to represent the problem.CCSS.Math.Content.3.MD.A.2

15. CCSS.Math.Content.3.MD.C.5 Recognize area as an attribute of plane figures and understand concepts of area measurement.CCSS.Math.Content.3.MD.C.5 CCSS.Math.Content.3.MD.C.5.a A square with side length 1 unit, called "a unit square," is said to have "one square unit" of area, and can be used to measure area.CCSS.Math.Content.3.MD.C.5.a CCSS.Math.Content.3.MD.C.5.b A plane figure which can be covered without gaps or overlaps by n unit squares is said to have an area of n square units.CCSS.Math.Content.3.MD.C.5.b CCSS.Math.Content.3.MD.C.6 Measure areas by counting unit squares (square cm, square m, square in, square ft, and improvised units).CCSS.Math.Content.3.MD.C.6 CCSS.Math.Content.3.MD.C.7 Relate area to the operations of multiplication and addition.CCSS.Math.Content.3.MD.C.7 CCSS.Math.Content.3.MD.C.7.a Find the area of a rectangle with whole-number side lengths by tiling it, and show that the area is the same as would be found by multiplying the side lengths.CCSS.Math.Content.3.MD.C.7.a

16. CCSS.Math.Content.3.MD.C.7.b Multiply side lengths to find areas of rectangles with whole-number side lengths in the context of solving real world and mathematical problems, and represent whole-number products as rectangular areas in mathematical reasoning.CCSS.Math.Content.3.MD.C.7.b CCSS.Math.Content.3.MD.C.7.c Use tiling to show in a concrete case that the area of a rectangle with whole- number side lengths a and b + c is the sum of a × b and a × c. Use area models to represent the distributive property in mathematical reasoning.CCSS.Math.Content.3.MD.C.7.c CCSS.Math.Content.3.MD.C.7.d Recognize area as additive. Find areas of rectilinear figures by decomposing them into non-overlapping rectangles and adding the areas of the non- overlapping parts, applying this technique to solve real world problems.CCSS.Math.Content.3.MD.C.7.d CCSS.Math.Content.3.MD.D.8 Solve real world and mathematical problems involving perimeters of polygons, including finding the perimeter given the side lengths, finding an unknown side length, and exhibiting rectangles with the same perimeter and different areas or with the same area and different perimeters.CCSS.Math.Content.3.MD.D.8