Who is the tallest?
Who is the shortest?
How can we find out?
I also placed some non-standard units for length (cubes and Kapla planks) as well as standard units of length (measuring tapes) for added exposure.
As students made their way into the classroom, I sat back and observed. I was excited to see what they would do and use to answer the questions.
A few students read the questions out loud to everyone. They were very excited and quickly started to stand back to back to figure out their height in comparison to their friends. I was surprised that they took a different solution to figuring out the questions than I had anticipated. They didn't use any of the materials I set out. Instead, they worked as a group sorting and lining themselves from tallest to shortest in a line!
I was very proud of the way they self managed and used their critical thinking skills to find the answers to the questions without any guidance.
But now I wondered how to motivate them to use the materials to measure length. They were no longer interested in measuring each other since they answered the questions posed to them.
I decided to add more to the existing provocation and use their interest of building tall structures as a possible motivator for them to use the measuring materials. I posed new questions:
How tall is your structure?
How can you find out?
They enjoyed using the non-standard units of measurement, but were particularly drawn to the rulers and measuring tapes available. I guided their learning by demonstrating the correct way to use a ruler and measuring tape. They wondered why there were numbers on both sides, so I showed them and explained the difference in spacing between the lines of one side versus the other. I didn't go into deep conversation about millimeters, centimeters and inches, but asked them to choose which side they wanted to use to measure their structures.
After a few days, I noticed that the interest in measuring structures was fading, maybe it wasn't meaningful to them or they didn't see the purpose for it. Instead students started measuring random objects and each other. I took this opportunity to once again change the provocation questions:
What can you measure?
What can you use?
During a group discussion on measurement, H. S. came up with a wonderful theory!
"If you're tall you have a bigger shoe and if you're smaller you have a smaller shoe."
I asked the students how we can find out if H. S.' theory is correct? They began measuring their shoes and then each other to find out. I felt this was a perfect opportunity to discuss the importance of using the same measuring material (constant non-standard unit) when comparing length.
"Just as it is important for students to have opportunities to measure a length using different units, they need to measure different lengths using the same unit. This will give them measurement data that they can readily compare."
-Big Ideas from Dr. Small, pg. 93
I started thinking about the exposure my students have had to measurement thus far. I couldn't help but feel like something was missing. Something I try my best to do as an educator is make a link between learning in the classroom and it's applicability to our daily lives and the world around us. So I decided to ask the students the simple question:
"Why do we measure?"
"So we know how tall you are." F. D.
"Cause they don't know how old you are and they're gonna wonder how tall you are." B. K.
"My cousin is five and I am four and I am taller than him." Z. G.
"We measure how tall we are." S. T.
"So we know how tall we are and how many bones we have because so our doctor knows how much we have grown." S. C.
"If some people are working and are putting in a new door, they have to measure how tall the door is so they know if the door will fit in the doorway." C. C.
"They use a measuring scale that measures height." M. O.
"How do we measure the weight of the class?" W. E.
"When my brother was in my mom's tummy, he came out before me, but I'm taller than him." E. E.
"So people know how big you are cause people want to know how tall you are." K. W.
"You can measure their weight with a measurer. It has a line thing and it's at my doctor's. S. C.
"He wants to know if you're too much weight or not enough weight. It's called a scale. It touches your head and a silver thing goes down." J. K.
"There's different kinds of scales because at my home I do have a scale and you just step on it and it tells you how heavy you are." H. S.
"B (brother) was born first and he's taller than me." M. S.
"I think if you are born first, whoever is born second they are bigger." E. E.
"It depends on who is born first in your family. A (sister) is six and she was born first and she's tallest." M. O.
"I was born first and I'm taller than my brother." C. C.
"But Z. G. is four and I'm four but he's taller?! M. S. is four but he's taller than me still!" E. E.
"J. S. is five and I'm four and I'm taller." O. M.
"D. A. is five and Z. G. is four and Z. G. is taller!" W. E.
"Maybe people get born at not the same time, that makes a difference of how old people are?" O. S.
The students' responses gave me a better idea of the knowledge they had about measurement. They seemed to be aware that measuring also entailed mass and time, not just length.
The discussion of age and its relation to height also continued to be debated by the students. This led to the co-creation of a chart displaying their name, age, and height.
After the chart was completed, we studied the data together. Students noticed that being older didn't necessarily mean they were taller. Someone who is older can be shorter than someone who is younger.
"There is examples for both theories! It tells me maybe both are right!" Z. G.
"Maybe families are different sizes because not everyone is born at the same time." O. S.
"Maybe different families get different things?" M. O.
"I think it depends on how much you eat and how much you grow." H. S.
I am glad I asked the question, "Why do we measure?". It provided insightful responses and generated a purposeful investigation that was meaningful to the students and motivated them to further develop their measuring skills.