Outside is In: Clearing the Muddy Waters
Posted by Martin Fortin
“Outside is In”
Here’s a lab oriented lesson from the Cispus Learning Center about water quality that can be done at in the classroom or at any outdoor school…“Clearing the Muddy Waters”
CLEARING THE MUDDY WATERS
Focus: To develop the concept of sedimentation as a flip side to erosion
Group Size: Entire class
Time Required: Initial 5 minutes
Follow up: 5-15 minutes later during the same day, or next day
Materials: Pebbles, Clay, Fine, Sand, Silt, Coarse sand, Clear glass jar with a screw top
Setting: Physical Classroom
Fill the jar half full of water. Finish filling the jar with about equal parts pebbles, coarse sand, fine sand, clay, and silt (or any combination that is available). Shake the jar and then allow to sit undisturbed.
Discuss how water erodes a mixture of dirt, sand, and rocks. Discus what students think will settle out first and why.
Wait an hour or more and compare student predictions with actual results. Students could draw the layers, with measured thickness and appearance (color, texture). This serves best as a lead in for field observations.