Comparison Matrix for Abrasion Results

This data chart is very robust and help students collect and organize data as well as helping students to begin the analysis of data. Determining Similarities and Differences is also an excellent way to deepen understanding. Using the comparison matrix as a data collection device and a graphic organizer will help students to write better conclusions at the end of an inquiry activity.

Comparison Matrix for Abrasion Results
Characteristics	Samples to be Compared: Brand X Vinyl Tile Squares tested for abrasion resistance to various grits
	60 grit	100 grit	150 grit
1. Color	In the abraded area were different colors of brown from a pale light brown to nearly white.	The abraded area was a tan color and fairly uniform.	The abraded area was light brown and in some parts of the abraded area there was hardly any color change.	Similarities: all samples became lighter after abrasion.
				Differences: The bigger grit caused changed the color more dramatically from brown to very light pale brown. The 100-grit was a tan color and the 150-grit sample was a light brown.
2. Texture	You could feel slight to deep scratches.	You could feel, a slightly rougher texture from the area not abraded.	You could hardly feel the difference from the area not abraded.	Similarities: all 3 felt less smooth
				Differences: As the grit size increased, the texture changed more.
3. Surface Destruction	There was a lot of destruction. The abradant removed the vinyl top in some areas.	You could see thin lines that cut through the surface of the vinyl.	You had to look really close to see the abrasion. Surface was pretty much in tack.	Similarities: The 100 and 150-grit caused minor surface destruction
				Differences: The 60 grit paper caused visible damage to the surface.
4. Number of strokes with the abradant	10	30	60	Similarities: None
				Differences: The sandpaper with larger grit pieces caused abrasion faster

Comparison Matrix table is from Marzano, R. J., Pickering, D. J., & Pollock, J. E. (2001). Classroom instruction that works: Research-based strategies for increasing student achievement. Alexandria, VA: Association for Supervision and Curriculum Development.

Comparison Matrix
Characteristics	Items to be Compared:
	Sample #1	Sample #2
1.			Similarities:
			Differences:
2.			Similarities:
			Differences:
3.			Similarities:
			Differences:
4			Similarities:
			Differences:
5.			Similarities:
			Differences:
6.			Similarities:
			Differences:

Similarities and Differences

Name: _____________________________

Overlapping circles illustration