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Pre-K through Grade 2
Grade 3 through Grade 6
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Grade Levels Grades 3 through 6
Estimated Teaching Time 15
minutes
Interdisciplinary Connections
- Observing a simulation of epidermal cell loss (Science)
- Telling personal stories (Language Arts, Social Skills)
Objectives
Students will learn what the epidermis is and how it functions
as part of their skin.
What Students Do
Students will observe a simulation of how the epidermis is rubbed
off, and gain an understanding of how it repairs itself. They will
also relate stories of their own experiences.
Materials Required
- Bar of soap
- Coarse sandpaper
- Sheet of paper, a contrasting color to that of the soap
Advanced Preparation
None.
Suggested Sequence
- Ask students how many of them have ever gotten sunburned, which
then caused their skin to peel? Ask them what was under that layer
of skin that came off their bodies? [More skin.] Explain
that skin is an incredible regenerator. Tell them to pretend that
the bar of soap is a human being that has an epidermis.
- Hold the bar of soap and the sandpaper over a sheet of paper.
- Gently rub the soap up and down with the sandpaper.
- Tell students to watch the outer layer of soap flake and fall
onto the paper. Explain that the same thing happens to our skin
when rubbed by rough objects. Human skin is rubbed away daily.
- Explain to students that the very top layer of epidermis is
made up of dead cells that simply fall off when touched. Explain
that when our epidermis is rubbed off, those cells are replaced
by the layer beneath it, which creates new cells to replace the
lost ones.
- Explain to students that when they get sunburned it is actually
the living cells in and beneath the epidermis that get burned;
when too much sun destroys those cells, we can feel pain. Tell
them that’s why it’s important to protect skin from
the sun with a sunscreen. Finally, explain that once the bottom
layers of epidermal cells are regenerated, their skin will peel
off and be mended.
- Ask students how many of them have ever had a cut? What happened
to the opening in their skin? Explain that when skin gets cut,
the cells grow back together making it heal.
- Lead students to the conclusion that because our epidermis is
constantly changing and repairing itself it keeps our skin fresh
and in good condition.
Interesting Fact Much household dust is actually
old skin cells.
Check for Understanding
Ask the following questions:
- How does our epidermis help us?
- What is one of the ways we can see skin repairing itself?
Extensions
- Students could try rubbing a block eraser and watch the eraser’s
“epidermis” rub off. Then ask them to wet a thumb and rub
it back and forth over a forearm. Can they loosen a little roll of skin?
- If a student in class has a cut, make daily observations of how the
epidermis repairs itself.
- Students could research other living things that shed or lose layers
of their skin.
Words to Share
- Dermis
- Epidermis
- Sunburn
- Sunscreen
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