Weekly Homework: Sept

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Name:______________________
Weekly Homework:
March 2 – March 9
A. Math: There will be math homework Monday - Thursday this week.
B. _____Writing: Write a short story, either fictional or real, with one of the themes we
discussed in class this past week. Themes: honesty, compassion, perseverance,
cooperation, loyalty, kindness, courage, acceptance, patience, and forgiveness.
C.
Reading Comprehension: Volcanoes! Read the attached short articles about
Volcanoes. Answer the questions. The Word Search is optional.
D. ___ READ, READ, READ and complete the Home Reading Log. A minimum of 125
minutes per week is required. These minutes will go toward the Penny Creek 1,000 minute
reading challenge!  FRIENDLY REMINDER: GET IT SIGNED BY A PARENT.
Home Reading
Log
NAME:
Date Book Title (Remember to Capitalize titles)
Number of min.
A minimum of 125 minutes. All minutes will go toward the Penny
Creek 1,000 minute reading challenge! 
Total minutes read this week __________________
Parent Signature ____________________________
Three Kinds of Volcanoes
SHIELD VOLCANOES have gentle slopes, like a shield,
because they are made of many layers of a kind of
volcanic rock that flows easily when melted. This kind
of rock is called BASALT. When it flows out of the
vent it forms thin layers sloping away from the crater.
Some shield volcanoes get to be very large. The
volcanoes which make up the islands of Hawaii are
shield volcanoes.
CINDER CONES are made of bits of kind of volcanic rock called
ANDESITE. Sometimes there are bits of basalt, too. These bits of
rock are called cinders. They may be tiny, like ash, or larger, like
gravel. They get blown out of the vent and harden in the air. When
they land, they pile up around the crater to form a steep cone. Cinder
cones are often smaller than shield volcanoes, and they wear away
easily.
COMPOSITE CONES are made of layers of cinders
between layers of lava. The layers of cinders make
the sides steep, and the layers of hardened lava keep
them from wearing away fast. Many famous volcanoes
like Mr. St. Helens in the State of Washington are
composite cones.
1. Composite cones are often bigger than cinder cones because.
a. they are older and have had more time to grow
b. the hardened lava keeps them from wearing away fast.
c. they grow where there are already mountains.
2. After a shield volcano erupts, it usually is
a. a little higher because most of the lava runs down the sides of the volcano.
b. a lot higher because most of the lava piles up around the vent.
c. lower because the top of the volcano will cave in.
3. Mr. McKinley in Alaska is one of the world’s highest volcanoes. From its size we can tell that
a. everything in Alaska is big.
b. Mt. McKinley is a cinder cone.
c. Mt. McKinley is not a cinder cone.
What Makes Volcanoes Explode?
When you look at pop in an unopened bottle, you can see a
few bubbles of gas in it, but not many. Shake the bottle
and take off the pressure cap. Out comes thousands of
bubbles bringing a shower of liquid with them. The pressure
kept the gas dissolved in the liquid. When you took off the
cap, the pressure of the gas made it suddenly come out of
the solution and explode out of the bottle.
The hot magma underneath volcanoes has a lot of gas dissolved
in it, too. The rocks on top press down and keep the gas
dissolved. Then when something takes the rocks away, the gas
suddenly comes out of solution and explodes out of the volcano.
Rocks and hot lava come with it.
Cinder cones are more dangerous than shield volcanoes because the magma under cinder cones
is made mostly of a kind of rock called ANDESITE which can dissolve a lot of gas. This makes
cinder cones very explosive. The magma under shield volcanoes, like those in Hawaii, is made
mostly of a kind of rock called BASALT which can dissolve only a little gas. This makes shield
volcanoes less explosive. When shield volcanoes erupt, people have time to get out fo the way
because the magma doesn’t explode. It flows.
1. Cinder cones are more explosive than shield volvanoes because
a. the magma under them can’t absorb much gas.
b. the magma under them can absorb a lot of gas.
c. the magma under them is hotter than the magma under
shield volcanoes.
2. When the magma under a volcano is mostly andesite, the lava that
comes out during an eruption will
a. flow out.
b. explode out.
c. bubble out.
3. From the story you can tell that
a. pop got its name from the way it pops out.
b. there are more cinder cones than shield volcanoes on earth.
c. cinder cones are different from shield volcanoes because
the magma under them dissolves gas differently.
Deep Under A Volcano
No one can dig under a volcano to see what is underneath, but scientists
who study volcanoes have learned many ways to make guesses and check
them out. Many scientists agree that deep underground there is rock so
hot that it is melted. This melted rock is under so much pressure from
all of the rocks above that it is pushed up through cracks toward the
surface of the earth.
The melted rock is called MAGMA when it is still below the surface. The
pressure keeps it stiff, about like toothpaste, even though it’s melted.
If the magma is squeezed clear to the surface, we say the volcano ERUPTS.
Now the magma is not under pressure any more. We call this magma that
has come to the surface LAVA. Lava is not under pressure the way magma
is, and this changes it. Now it can flow. Some kinds of lava, while red hot,
are almost as runny as water. The lava that makes the volcanoes of Hawaii
is this runny kind. The lava that is making a new dome in the Mt. St. Helens
crater is rather stiff even when it is red hot, so instead of flowing it pushes
up into a dome shape.
Look at the volcano in the picture and at the magma underneath it. You can
see that some of the magma is coming out at the top of the big cone, and
some of it is coming out through a crack in the side of the big cone and
making a little cone. Mt. Shasta in California has a smaller cone on one side
made this way. The smaller cone is names Shastina.
1. Magma is stiffer than lava because
a. it is hotter.
b. the rocks above press down on it.
c. it has stones in it and that makes it thicker and stiffer
than lava.
2. If lava flows through a forest,
a. the trees will become petrified.
b. the trees will burn.
c. the trees will stop lava.
3. From the story you can tell that
a. scientists have been reading a lot of books about volcanoes.
b. scientists have been digging underneath volcanoes.
c. scientists have been studying volcanoes carefully.
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