# How Do You Measure Up?

## Digital Camera Activity

4 and higher

### Objective:

To give students experiences in nontraditional measurement systems, measurement, data collection, data analysis, ratio and proportion, surface area and volume.

### Summary:

By photographing your students as they are lined up in front of a brick wall or other surface which had horizontal line pattern to it you can create a scaled record to be used for many mathematics lessons.

### Procedure:

On a well lit day, line as many of the students up against a brick wall which has easy to see horizontal lines in it. If one is not available on the school campus take a field trip to some large building like a library or bank that is close by. Also document the actual spacing of the lines on the wall before leaving. Once in the class, retrieve the photo and make enough copies so each group of students has at least one.

Create activities which require the students to draw horizontal lines on the photos using the brick lines to create a vertical scale. Simple lessons at lower grades could ask the following questions: What is the ratio of students who are taller than Joe to students shorter than Joe? (Draw the line at Joe's height and compare heights to answer it.); What's the ratio of girls taller than Joe to girls shorter than Joe? ...boys taller than Joe to boys shorter than Joe?, etc. Interesting questions could involve students the same height as Joe. Students might estimate how many Joes it would take to equal the height of the building.

Other students with more skills might try to answer how tall the building is, how long the wall is or how many bricks are in the wall.

You could define a 'Joe' as your unit of measure. This could lead to lessons requiring students to organize a whole measurement system that would help them better understand the metric system. Maybe one Joe is not the best unit on which to base a measurement system. They could decide what they prefer to use by some democratic means. An important discussion which would probably come up would be how to break up the unit into fractions of a unit. Which is better? Decimal portions or fractions based on one-half , one-fourth, one-eighth, etc? Once the unit is chosen, they could use the camera to photograph several convenient items to be included in a booklet. They could take front, right side and top view photos. They would use their unit of measure and create a complete set of vital statistics for their objects including all measurements. Students can draw dimensions right on the digital photos which are included in the reports. Depending on the level of skills, they could calculate surface areas and volumes. Word processing programs could be used to produce the reports and simple spreadsheets could be used to automate the surface area and volume calculations. They must be sure to include photos of the master unit of measure in their booklet.

### Assessment:

Introduce a new common item like a pencil or a paper clip to be defined as the master unit of measure. Have students measure your test set of items with the new master unit. Use the camera to document the items and produce photos with the dimensions drawn on them. Include a photo of the master unit. Increase the requirements as allowed by the skills of the students.