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Caitlin O’Connor
5-E Lesson-Rock Cycle
7th grade
Objectives:
Given a variety of materials to create a crayon rock cycle, the seventh grade students will be able to identify how the rock cycle works
and be able to explain how one type of rock can be transformed into another type of rock within a time limit of 40 minutes.
PA Standards:
3.3.7.A1: Define basic features of the rock cycle. Describe the layers of the earth. Differentiate among the mechanisms by which heat
is transferred through the Earth’s system.
1.8.7.A: Develop, with teacher guidance, an inquiry-based process in seeking knowledge.
Concepts and Vocabulary:
Sedimentary rock
Erosion: when materials are removed from the surface and changed into something else
Sediment: is naturally occurring material that is broken down by processes of weathering and erosion
Metamorphic rock
Igneous rock
Magma
Rock cycle
Teacher Materials:
Each
group
will
need:
‐enough
crayons
for
each
person
to
get
at
least
one
‐a
couple
of
pencil
sharpeners, plastic
knives, or
other
grating
utensils
2
‐a
Styrofoam
cup
or
bowl
‐enough
foil
and
wax
cupcake
cups
for
each
student
To
share
with
the
entire
class:
‐source
of
hot, but
not
boiling
water (use coffee pumper)
-Sample rocks for the students to look at (Igneous, Metamorphic, and Sedimentary)
-Rock Posers (Rock Cycles, List of Rocks)
Teacher Resources:
http://measure.igpp.ucla.edu/GK12-SEE LA/Lesson_Files_10/Cam_Macris/CM_crayonrock_lesson.pdf
http://www.exo.net/~emuller/activities/Crayon-Rock-Cycle.pdf
http://www.sciencespot.net/Pages/classearth.html#Anchor6
Engage: One type of rock, such as igneous rock, can be transformed into another type of rock, such as sedimentary rock. Is this true or false?
What do you think? Ask the students to predict if rocks can be transformed into another type of rock..\Downloads\Rock Cycle Power Point!.pptx
1. Pass around samples of sedimentary rock. Ask students to observe the rocks and describe some of the similarities between
them. As students offer their ideas, write them on the board in one column. You should end up with a list like: First rock type:
can see grains, grains can be of different sizes, has layers or streaks, grains come off if you rub it.
2. Collect the sedimentary rocks then pass around samples of metamorphic rocks. Ask students to observe the rocks and
describe how these rocks are different from the sedimentary rocks. Again, write their ideas in a column on the board. You
should end up with a list like: Second rock type: no grains, has crystals, many colors, very hard, swirly patterns.
3. Collect the metamorphic rocks then pass around samples of igneous rocks. Ask students to observe the rocks and describe
how these rocks are different than the other two types of rocks. Again, write their ideas in a column on the board. You should
end up with a list like: Third rock type: no grains, some have crystals, some have lots of holes, uniform texture and pattern
throughout the rock, no layers or swirls.
4. Tell the students that they have been observing and categorizing the 3 major types of rocks: sedimentary, metamorphic, and
igneous rocks. Explain that today, they will be using crayons to model the processes that create each of these 3 types of rock.
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Explore: Divide Students in groups of three or four and pass out materials/rock cycle handout.
1. While looking at the 3 descriptions on the board (See Poster), give each group a sample of a crayon rock. Which one is this
sample most similar to? It doesn’t have grains, layers or streaks. It is an igneous crayon rock! On their handout, in the box at
the top of the circle, have students write “igneous rock”.
2. The first step is to create sediment. Have students un-wrap their crayons then create a pile of crayon shavings on their piece of
aluminum foil by using a pencil sharper or a plastic knife. They may trade crayons among themselves to acquire a mixture of
colors. Give them around 5 minutes to build up a decent sized pile.
3. On the diagram, the arrow from “igneous rock” can be labeled “erosion”. The next box can be labeled “sediment”. (See
Poster)
4. Now fold over the foil to wrap up the sediment pile. Press down on the pile as hard as you can. Gently unwrap it. The
sedimentary crayon rock will be fragile but should hold together in a packed layer.
5. Have students rub their hands together to create pressure and heat.
6. Each student should place their fragile rock into their hand. Students should cup their hand and begin to apply pressure and
heat using their thumb. Have the students apply pressure for 60 seconds.
7. Discuss the similarities between the metamorphic crayon rock and the real metamorphic rocks the students observed earlier.
8. On the diagram, the arrow from “sedimentary rock” can be labeled “metamorphism – heat and pressure transforms the rock”.
The next box can be labeled “metamorphic rock”. Discuss this process as it occurs in the real world with rocks being subjected
to intense heat and pressure beneath the surface of the Earth.
9. Go around and fill each cup with hot water. Also, fill a separate cup with cold water. (Use a coffee pumper from the cafeteria)
10. Each student should put their metamorphic crayon rock in the foil boat and float it on the hot water. This time, allow the wax
to melt until a smooth pool of liquid wax forms and the colors blend together uniformly. Carefully remove the foil and let the
igneous crayon rock cool.
11. Discuss the similarities between the igneous crayon rock and the real igneous rocks the students observed earlier.
12. On the diagram, the final arrow from “metamorphic rock” can be labeled “melting into magma then cooling”. Discuss this
process as it occurs in the real world with rocks being melted deep within the Earth then extruded again as volcanoes or
bubbles of magma that do not reach the surface.
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Explain:
1. Ask the students if they think this igneous rock could be turned into sedimentary rock? How?
A: Erosion into sediments and compacted into sedimentary rocks.
2. Could it be turned directly into metamorphic rock? How? Could a metamorphic rock be turned directly into sedimentary rock?
How?
A: Yes, through heat and pressure. Metamorphic rock can be turned directly into sedimentary rock through erosion into
sediments and then compaction into sedimentary rocks.
3. Add additional arrows across the middle of the rock cycle to illustrate that any type of rock can turn into any other type of
rock. For example, metamorphic rock can be eroded into sediment then compacted and cemented into sedimentary rock. (See
Rock Poster)
Elaborate:
Students will create an elaborate rock cycle. Have students work in groups to research WHAT types of rocks transform into
other types of rocks (for example, the sedimentary rock limestone transforms into the metamorphic rock marble). Students
will share their findings with the class.
Evaluate:
I will pass around a copy of the misconception question (One type of rock, such as igneous rock, can be transformed into
another type of rock, such as sedimentary rock). Students will have to circle True or False and provide scientific reasoning
below their answer. They will be graded based on the rubric attached below.
4 points- Circled the correct answer (true) and used rock cycle or concepts related to the misconception statement in the
explanation.
3 points-Circled the incorrect answer (false) but correctly answered the misconception statement in the explanation.
2 points-Circled the correct answer (true) with little or no explanation.
1 point-Circled the incorrect answer (false) with little or no explanation.
0 points-No attempt or response to the misconception statement.
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Directions: The rock cycle illustrates the ways rocks change from one form to another. Rocks are constantly undergoing weathering, melting
and being altered to form new rocks. The diagram below is a great way to illustrate the connections between these processes. As you know there
are three types of rocks: igneous, metamorphic, and sedimentary. Write the correct word in the blank next to the rock type. Also, place the
terms sediments and magma in the correct places. There are several different processes in the rock cycle which cause rocks to change form.
Write the terms melting, heat and pressure, compaction, cooling and erosion in the correct blanks. Fill in these terms as you proceed in a
clockwise direction on the diagram. Once you have done this you have created a finished map of the rock cycle.