Slow Rot…or Not!
Grade level: 5
Rationale: In this lesson, students will discover how various environmental conditions affect materials that easily decompose, and how that relates to artifact preservation, such as ancient sandals made of plant fibers. They will formulate and directly investigate their own preservation theories by observing how grapes decompose in five different environmental settings. They will hypothesize how particular environments will affect their “artifact,” record observations of the grapes’ changing properties over a ten-day period and, finally, form conclusions based on their research.
Lesson Duration: 10 days
Texas Essential Knowledge and Skills (TEKS):5th Grade
Step 1: Display the picture of the ancient sandal on an overhead projector. Explain that ancient people made these sandals more than 5,000 years ago out of plant leaves, such as yucca and agave. Discuss how they could have survived so long. What kinds of environment might have preserved them? (Examples: beach; dry cave; jungle; river bank; arctic; desert; ocean, etc) Note: this sandal was found by archeologists in a dry cave in the Chihuahuan desert in the Texas Trans-Pecos region near El Paso. .
Step 2: Divide class into 5 groups. Pass out Observation Tables and small bunches of grapes to each group. Groups observe the grapes and fill in descriptions under Day 1 on the Observation Table..
Step 3: Assign one of five environments to each group. Students discuss the probable conditions they would expect in the environment assigned and then form a hypothesis about how well the grapes will be preserved (Students will record on Observation Table.).
Step 4: Group instructions for simulating five environments:
Step 5: Over the next 10 days, groups monitor the grapes and record changes periodically on Days 1, 5, and 10. They will need to both write and draw their observations. All students will observe and record.
Closure: Which environment best preserved the grapes? The dry cave closely matches the environment where the ancient sandal was found. Why would a dry cave preserve yucca leaf sandals better than it did the grapes?
Student Product: Which environment best preserved the grapes? The dry cave closely matches the environment where the ancient sandal was found. Why would a dry cave preserve yucca leaf sandals better than it did the grapes? After completing the 10 days of observation, each group shares their original hypothesis and their final conclusions with the class.
Extension Activity: Have the class explore the interactive “The Case of the 5,000-Year-Old Sandals” with Dr. Dirt, the Armadillo Archeologist www.TexasBeyondHistory.net/kids/sandals to learn more about ancient sandals of west Texas and how they were made.
Author: Jennifer Goldstein
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