What is Measurement?
Lesson 1 of 6
Objective: Know relative sizes of measurement units within one system of units including km, m, cm; kg, g; lb, oz.; l, ml; hr, min, sec. Within a single system of measurement, express measurements in a larger unit in terms of a smaller unit. Record measurement equivalents in a two-column table.
(My student have had many experiences with measurements, and tools.)
In this lesson, I want my students to understand just what it means to measure. I invite my students to the carpet to probe a little bit. I ask, “What things can be measured?” (Weight, height, length, food, etc…) You guys are exactly right! Well today I want you to focus on identifying measurable properties of different objects. Do any of you know what this means? Students give a blank stare! I pick of a measuring cup. I ask, “What can be measured using this tool?” I pick up a ruler. What can be measured using a ruler? I pick up a few more measuring tools to make sure students are thinking exactly what is intended in order to understand what it means to measure.
Now, I want to push you guys a bit today! What I mean by that is I want you all too really focus on measurement being an approximate tool of identifying properties of objects. This means that it is not exact like adding or subtraction.
This lesson will focus on the following Mathematical Practices:
MP.5. Use appropriate tools strategically.
MP.6. Attend to precision.
MP.7. Look for and make use of structure
In this portion of the lesson, I want students to connect to measurement. I write these focus questions on the board.
What tool could you use to find your answer?
Is there another tool you could use?
Why did you use this method to solve the problem?
Then, I ask can anyone think of a time at home, or while out and about that you have used measurement. Some students say; I weigh myself; I weigh fruit, measuring food, and turning up the volume on the radio. I say, what about when you have a fever. What can you measure? Temperature
Think about a time when you had to wrap a gift, or poured a cup of water. All of the things above are easily identifiable as measurement situations. However, what is the commonality between all of these comparisons? Some students see that all of the situations are measurable. I want you guys to move into your assigned groups. Choose two situations from the board. I want you all to discuss the following:
What steps must you take? What tool could you use? Is there another way to measure? Why did you use this method to solve?
MP5- Use appropriate tools strategically.
As students are working, I circle the room to see what students are thinking. For instance, some students choose to explain the tool used for measuring weight. I ask students, what tool did they select. (Scale) They went on to explain they chose a scale because it measure in pounds. Some students noted that they can also measure in kilograms. I ask them to explain. They connect to times they went grocery shopping. They notice that they weighed fruits on a scale; however, it did not weigh in pounds. So, they seem pretty clear about selecting the appropriate tool and how and why they are used.
I ask students to be ready to explain and share their work with the rest of the class.
Rap it Up!
To get students to think about how and why they use measurement in school, I give each group a bag of measurement tools to investigate. First, I ask what does it means to measure. (To give the size, or weight of something.) Then, I ask students to take one of the items out of their bag. I ask them to take five minutes to discuss the attributes o the object. For instance: I want to see if they can determine how they look, feel, or how heavy. Are there any attributes that be measured? If so, how and why will you measure them? While students are working, I circle the room to see what students are thinking. I want to know what objects would be a bit more difficult to measure, and what measuring tools would most likely be best. Students seem to find it hard to measure things that did not go along with measuring tools. I tell them that is is ok! Sometimes some objects can not be measured with tools. I continue to monitor students as they work in their groups. I make sure I continue to probe them to see exactly what they are thinking and why. I encourage students to ask questions and share out their learning experiences. I use their responses to determine if they have grasped the intended learning outcome.
After that, I ask students to write a summary about what we discussed in their math journal.