Safety Considerations: Remind students not to throw objects, or use the meter sticks as swords, etc.

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1 Metric Scavenger Hunt Author s Name: Seth Shelnutt, Heather McNeill, Erin Case and Gloria Weber Teaching Partner(s): Xavier Monroe & Cassaundra Haggard Date of Lesson: 2/8/2011 Length of Lesson: 45 min. Grade Level: 5th Source of the Lesson: Math + Science: A Solution, AIMS Education Foundations, 1987 Florida Sunshine State Science Standards Addressed: Benchmark Number Descriptor MA.5.G.5.3 Solve problems requiring attention to approximation, selection of appropriate measuring tools, and precision of measurement Concepts: Being able to approximate measurements and have an understanding of size and scale is a crucial skill. If one were to be asked to cut a piece of rope that is 6 feet long, being able to estimate the distance quickly allows you to measure it faster and cut it faster. The key to approximation is knowing the size of objects and being able to compare objects to one other. If you know that a piece of paper is 11 long, and your textbook is a little bit longer than a piece of paper you could estimate that your textbook might be 12 long. Knowing approximately how long or wide an object is, also allows you to select an appropriate tool to measure with. If you are measuring a pencil, a centimeter ruler would be a better choice than a meter stick. Materials List and Advanced Preparations: Metric Scavenger Hunt class set (From AIMS book) Metric Measurement Evaluation class set Photo of Justin Bieber s tour bus (can either be electronic, or a hard copy) A centimeter/ millimeter ruler for each student A meter stick for each student (may have to group up if there aren t enough) Performance Objectives: Students will be able to determine which tools are more appropriate in measuring different objects. Students will be able to approximate the size of an object. Students will be able to state the precision of their measurements. Safety Considerations: Remind students not to throw objects, or use the meter sticks as swords, etc.

2 Lesson Plan in 5E format: Engagement The teacher(s) will introduce themselves to the class and let them know that today they will be learning about approximation and measurement. Present the class with this scenario: Have you heard of Justin Bieber? Well he contacted me and said that he needs our help with something. Have you heard of Justin Bieber? You think we can help him? The question Justin needs us to answer is how long his tour bus is. (show picture) Can you guys guess about how long it is? Those are great estimates, but are they exact? Justin wants the exact length. How can we calculate the length of his bus? Measure it with what? Yes! Time: 5 minutes 20 feet, 50 yards, etc. Go to it and measure it. A tape measure, a yard stick, etc. Could I use this centimeter ruler? (hold up centimeter ruler) Yes, but it would take a really long time! Why would it take so long? Oh, okay so it would be a better choice to choose a larger unit of measurement? Because it is so small and the bus is so big. You need something that is bigger. Yes.

3 Exploration Show students the units of measurement (meter, centimeter and millimeter) explain the relationships between the units. Use actual objects to show the difference between units. Pass out Metric Scavenger Hunt to each student. Explain to the class that they are going to walk around the classroom and find objects that they think are near the listed lengths. Point out that some things will be measured in meters, some in centimeters and some in millimeters. The teacher may want to suggest that the students first find all their objects and fill in the object s name and then find the actual measurement. When the students return to their seats they can find the differences and fill in the last column. Then pass out the centimeter rulers, millimeter rulers and the meter sticks. Some students may have to share or take turns with the meter sticks if there are not enough for each student. The teacher should wander around the classroom making sure that students Do you know the difference between a meter, a centimeter, and a millimeter? Have you ever placed a paperclip on a meter stick/measuring tape? Let s each get a paperclip and measure it. Did we need the entire meter to measure it? What about a centimeter? If we place the paperclip on its side and measure the width of the wire, what units of measurement are we using? Now that we ve done that, look at the meter stick and you can see that there are 100 centimeters in a meter and 10 millimeters in each centimeter. How many millimeters do you think are in a meter? What unit of measurement would you use to measure the height of your desk, meters, centimeters, or millimeters? How about your pencil? How about the width of a piece of string? Now we re going to pass out a scavenger hunt, rulers and meter sticks. In the left column are measurements Time:15 minutes Maybe, it has been a while since we ve learned that. No, never thought to do that. No, we did not use the entire meter stick. Yes, the paperclip is about a centimeter. Wow, we re using millimeters. A million, ten hundred, a thousand Meters Centimeters Millimeters

4 are on task. Help students in need. As the students to return to their seats when they are done measuring the teacher should collect the meter sticks. (The teacher may want to leave the centimeter & millimeter rulers since they will be used in the Evaluation, unless they will be a distraction.) such as 40 cm. Can you find things around the room that you think are about that length? Write down the names of these items in the column next to it. We are now going to collect the meter sticks. Explanation Start an open discussion asking the students what they thought about their choices. You can go through the worksheet or select a few problems to discuss. What did you think about the math activity? What did you learn about units of measurement? What s the smallest unit? Okay, what about the largest? Time: 10 minutes It was fun! That there are some things we should measure in millimeters, some in centimeters and others in meters. Call on students to ask what they measured for some of the sizes and how close they were in their approximation. Let s go over what some of us got on the worksheet. Is there a volunteer to go over the first two problems? What did you measure? Yes. A desk. It was a little off but very close.

5 Discuss what the difference means. Now have the students explain why they chose the tool they did to measure each object Ask the students why we would use one tool over another. Draw from the students that one tool might be more appropriate for different measurements. How close was your approximation? Now that you re done measuring objects, do you think there are certain units of measurements we should use for certain objects? What units would you use to measure your book? Find the difference by taking the numbers from the approximation column and the measurement column and subtracting the bigger number from the smaller one. Put this is the last column. The difference from the approximation tells us how well we were able to choose the correct units of measurements. What does the difference tell us about the measurements? It s ok if we re not perfect in choosing the correct units of measurements but it s a good idea that we can choose the right unit of measurements to have a small difference. Why did you choose the measurements you did for the objects you measured? Why would we use one particular ruler rather than another? Yes. Centimeters. It was big so I used meters, it was small so I used millimeters, etc. The object was large so you needed the meter stick, the object was small so it was easier to use the small ruler, etc.

6 Discuss precision. The difference in rulers also varies in their precision. The smaller the ruler and the smaller the increments it has, the more precise the measurement will be. Elaboration Discuss different scenarios that one might have to choose which measurement tool would be best for the situation. Now that we have talked about differences. Let s talk about precision. The more information you have about something, the more precise your results are. If you measure how tall you are in meters are you exactly one or two meters or are you somewhere in between? Now if you measure in centimeters you can get a more exact answer and not have to round, so the smaller measurements are more precise. How accurate or precise do you think your measurements were? Given the choices of measuring in millimeters, centimeters, meters, or kilometers I need you to tell me which form of measurement would be the best choice. They were better with millimeters than with bigger units because you had to guess which it was closest to. Time: 5 minutes The first thing is the distance from the airport to your home. Kilometers. Why do you say kilometers? Because that is a long distance and it would take forever if we used meter sticks or anything smaller. Okay, what about the distance a slug moves in 1 minute. What about in 30 minutes? Answers are arguable, probably millimeters, then centimeters.

7 Evaluation See the attached evaluation, Metric Measurement Evaluation Instruct the students that they are to work individually and may use their centimeter/millimeter rulers. And then the last thing to measure is the height from the floor to the ceiling. Now that we ve have discussed how to use units of measurement and when to use certain units of measurements. Let s do a short exercise by ourselves to see how well we understand. A meter stick. Time:10 minutes

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9 Name: Metric Measurement Evaluation 1. If you were to measure the length of a car, what would you use? meter stick centimeter ruler millimeter ruler 2. What is the length of the following image? 3. Measure the length of the lizard. Use the line to measure the lizard. 4. The length of a piece of notebook paper is closest to which of the following? 28 millimeters 28 centimeters 28 meters