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Should you water a cactus?
Plant Adventures Unit | Lesson 4 of 5

Should you water a cactus?

Plant Adventures Unit | Lesson 4 of 5
Lesson narration:
Scroll for prep
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Discuss:

Why do you think the orchid is dying?

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Discuss: We have an empty square. Can you think of a plant that likes growing in lots of sunlight but little water?

missing plant

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Discuss:

What do you think is going to happen to the cactus if you water it every day? Why?

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Extensions

Below are ideas for extending this topic beyond the activity & exploration which you just completed.
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Extra Activity:

How a Cactus Stores Water

Using paper towels and wax paper, this simple activity shows students how the thick, waxy stems of cactus or the thick leaves of a succulent hold water.

If you have access to any succulents, bring in a few stalks and leaves. Let your students slice the leaves open and see the moist interior.

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Extra Activity:

A Plant with a Water Tank

The bromeliad, a plant that lives in the rainforest, avoids the shade of the forest floor by growing on the branches of tall trees. Living high in a tree, the bromeliad can't get its roots into the ground. So it stores water in a bowl made of its waxy leaves. This water tank is home to frogs, as you can see in this video.

The pineapple is a kind of bromeliad that you can grow and experiment with in your classroom. Find out how at this site from the Rain Forest Alliance.

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Art Extension: Grassheads With Style

At Mystery Science, we couldn't resist adding a bit of style to our grassheads. If your class would like to do the same, you'll find plenty of inspiration online. Your grasshead could wear a mohawk or a cute little bow. You can add googly eyes, pipe cleaner eyeglasses, and paper clothes. The possibilities are endless.

Here are supplies you may need:

  • pipe cleaners (for eye glasses)
  • peel-and-stick googly eyes
  • construction paper for "clothes"
  • ribbons for hair bows
  • scissors for grasshead barbers and stylists
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Distance Learning: Substitute Activity

If you are learning remotely, you can read about cacti and their adaptations.

Assign pages 4-14 in Prickly Plants, an Epic! digital book.

Ask students to discuss: “Why do cacti have spines?”

Ask students to draw their favorite cactus.

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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
earth by Calvin Hamilton
Desert by Roger469
cactus by NPS.gov
Africa cactus by John Atherton
Pink orchid by Arad
orchid by Dave Clode
aloe leaves by Raul654
orchids in window by Genie Schreiner
Flying duck orchid by Peter Woodard
aloe plant orange flower by Erin Silversmith
dying/yellowing orchid by tanie51
cactus upclose by chcidoameriky.cz
making aloe vera gel by Sarit Dangmaneerat
aloe on hand by
round cactus by NPS.gov
bottle of aloe gel by Fruit of the Eart
cactus on table by Loree
Yellow orchid by H. Zell
desert plants by Maria Nikolajeva
potted cactus by cowgurl160
Boabob tree by JialiangGao www.peace-on-earth.org
Orchid seed pod by Sunil Elias
desert scene by John Morgan
ferns on forest floor by Doug Lee
water a cactus by Zdenko Zivkovic
fern leaves by Sanjay ach
orchids in a field by Fritz Flohr Reynolds
shade loving plants by Peter Herpst
field of cacti by NPS.gov
ferns and hostas by Lynne Gordon
living room by MIchelle
cactus at night (lightening) by Pete Gregiore
Lesson narration:

Grade 2

Plant Adaptations

Adaptations & Habitat

2-LS2-1, 2-LS4-1

Activity Prep

Print Prep

In this lesson, students will learn that plants have different needs in terms of sunlight and water. In the activity, Grass Head Revisited, students will examine the Grass Head they made in the previous lesson. Earlier, they predicted which way the grass would grow. Now they will discuss what happened and why.

Preview activity
COVID-19 Adaptations
Digital alternative to activity

Students at home
Students at school
Students at home / at school
Assign pages 4-14 in Prickly Plants, an Epic! digital book. Ask students: “Why do cacti have spines?” Ask them to draw their favorite cactus.

Exploration

19 mins

Wrap-Up

1 mins

Grade 2

Plant Adaptations

Adaptations & Habitat

2-LS2-1, 2-LS4-1

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