Los Angeles Unified School District
Office of Curriculum, Instruction, and School Support
INTERIM ASSESSMENT
Grade 8 Science
Instructional Component 1
2014-2015
Student Test Booklet
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 1- Motion
Read the following passage carefully then answer the questions below.
Have you ever wondered about the Chinese zodiac and how the animals were chosen? The
legend is an interesting one. Each Chinese zodiac sign and the order they rank in was decided by
the mythical Jade Emperor. When the task of choosing the zodiac animals fell to the Emperor, it
was decided that the best way would be to arrange a race across the river. The order in which the
animals arrived would decide who would be second, third, fourth, and so on.
All the animals gathered at the bank of a river. The Jade emperor watched the race from
the opposite river bank. To help him judge the progression of the race, he had his servants set up
buoy markers every 20 meters (m). Here is an account for one of the races that took place
between an ox and a pig.
The race began. At the 40 second mark, the emperor asked for a status update from his
trusted advisor. The ox travelled at a constant speed and was at the 80 meter mark. The pig
moved at a rapid pace and he was in the lead at the 120m buoy. The pig saw that he was in the
lead and decided to take a nap for 20 seconds. Unknowingly to the pig, the ox caught up to him
during his nap by travelling at the same constant speed. The two animals raced neck in neck for
the next 60 meters so that they reached 180 meter mark at 90 seconds. The ox continued the race
at the same constant speed until they reached the 200m finish line.
This frustrated the pig. He decided that he would take a 50-second break and have a
snack to rebuild his energy so that he could beat the ox. But he was so full, that he actually ran
slower than he did when he was racing next to the rat and the ox. He reached the finish line in
160 seconds.
This story is a modification of “The Great Race: The story of the Chinese Zodiac”
(http://www.char4u.com/article_info.php?articles_id=199)
1
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 1- Motion
1. Using the information in the story, graph the race results for the ox and the pig.
Position (m)
Ox Race Results (m)
220
200
180
160
140
120
100
80
60
40
20
0
0
10
20
30
40
50
60
70
80
90
100
110
Time (s)
2. Calculate the average speed of the ox for the entire race. Include units and show your work.
3. Calculate the average speed of the pig for the entire race. Include units and show your work.
4. Calculate the average speed of the pig for each of the five segments of the race. Include units
and show your work.
2
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 1- Motion
5. At the beginning of the race, the pig was moving faster. How did the ox end up winning the
race? Use evidence from the reading and your graph.
3
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 2- Density
Read the following passage carefully then answer the questions below.
Plastics are materials composed of repeating chainlike-molecules called polymers, and are
usually derived from fossil fuels. Many everyday objects are made out of plastic. It is a material
that is often strong, lightweight, flexible and durable. Due to plastic’s durability and artificial
nature, it doesn’t biodegrade. It does however photodegrade, which means plastics are broken
down into smaller pieces by the absorption of light from the suns UV rays. Plastics of all shapes
and sizes, including the small pieces, end up in the water column as marine debris and can
entangle or are consumed by marine animals. It’s estimated than 90% of floating marine debris is
plastic.
Some plastics float in sea water, others sink and some remain neutrally buoyant. Density
is one factor that affects the buoyancy and location of the plastic debris in the water column.
Density is the ratio of a material’s mass to its volume. Density is the same value for a certain
type of material, regardless of the size of the object. Density can be calculated by dividing an
object’s mass by its volume. Density is an important property of all materials, whether solid,
liquid, or gas. It measures a material’s compactness, or how much mass is squeezed into a given
space. If plastic is more dense than sea water, it will sink. If it’s less dense, it will float.
Marine animals feed in different oceanic zones. There is the surface zone which is where
the water meets air and things float where they can be seen. There is the pelagic zone which is
where fish swim and plankton drifts. Finally, there is the benthic zone which is on or near the
ocean floor. Different plastics will impact different animals depending on the buoyancy of the
plastic and the zone in which the animal feeds. Some animals may become entangled in it while
others may consume it. One study showed that 267 species worldwide, including 86 percent of
all sea turtle species, 44 percent of sea bird species and 43 percent of marine mammal species are
impacted by marine debris (Laist, 1997). Sea turtles sometimes mistake sinking plastics for
jellyfish. Sea birds that dive into the pelagic zone to feed scoop up floating plastic fragments and
may even feed them to their chicks.
According to the Environmental Protection Agency, over 30 million tons of plastics were
thrown away in the United States in 2008. Some of this plastic ends up in the watershed and
ultimately, the ocean. People can help marine animals by reducing the amount of plastic they use.
Taking reusable bags to the grocery store, buying a reusable water bottle and buying products
with less packaging all reduce plastics in the waste stream. Supporting legislation that bans
plastic bags is another way to reduce marine debris.
Reading source
http://www.montereybayaquarium.org/lc/teachers_place/resources_teaching_activities.aspx
4
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 2- Density
1. The table below shows the mass and volume of four plastic items. Use the data in the
table below to calculate the density of each material. (Show your calculations using the
density equation).
Plastic Item
Mass
(g)
240
Volume
(cm3)
100
194
200
Plastic bag
9.8
10
Pipe
207
200
Vegetable oil
bottle
Milk jug
Density (g/cm3)
2.
Based on your calculation of the density of the various plastic items, determine which
plastic material will float or sink in fresh water and sea water?
Plastic Item
Sink or Float in
Fresh Water (Density=1.0
g/cm3)
Sink or Float in
Sea Water (Density=1.03
g/cm3)
Vegetable oil
bottle
Milk Jug
Plastic bag
Pipe
3. Explain how you determined which items will sink or float.
4.
Using your density calculations above, how will plastic bags and vegetable oil bottles
affect sea turtles and sea birds? Cite evidence from the text.
5
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 2- Density
5. You are hired as an environmental advisor, your bottled water company “Naive” is very
environmentally concerned. Based on evidence from the article, your calculations, and data from
the table, which plastic would you recommend your company use, that could make ocean clean
up easier?
6. Explain why a cube of steel with a density of 7.85 g/cm3 sinks and a boat with a steel frame
can float. 6
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 3- Forces
Read the following article and address the scenario below
4 Tips for Moving Boxes and Heavy Furniture
Author: K.C. Roads
If you’ve ever done a Do-It-Yourself move, you probably remember being very sore for a
couple of days afterwards—and that’s if you were lucky. If you weren’t so lucky, you might
have bruised your toes, strained your back or even twisted an ankle. So when you’re preparing
for your next move, it’s a good idea to learn as much as possible from professional movers so
you run the least amount of risk of getting injured. Here are some tricks of the trade for moving
heavy furniture and boxes.
1. Clear the path.
It’s so simple, yet so many folks forget to do it. Clear the walk space of all clutter and debris
ahead of time so you have plenty of room to maneuver.
2. Wear appropriate shoes.
Wear sturdy shoes with a good grip, especially when moving on and off a truck with a ramp.
This will prevent you from slipping and getting seriously hurt.
3. Use dollies or two-wheelers.
It’s a great rule of thumb that all professional movers live by: never lift when you can roll. Use
dollies or two-wheelers when you can to move boxes, furniture and other heavy items. Be sure to
use the straps and other safety equipment that come with them to prevent items from falling off.
4. Always practice caution!
Use common sense when lifting and carrying heavy objects, and forget about heroics. You don’t
want to be tied to a heavy object that can slip and take you with it. Study your packing list before
you start to lift and make the appropriate arrangements. If you have to use a piano sled, only do
so it you’ve got sufficient help.
Reading adopted from How-to-Resources.http://www.mymove.com/resources/moving/packing-unpacking/7-tipsfor-moving-boxes-and-heavy-furniture.html posted 09/15/2011
Activity Adapted and modified from:
http://phet.colorado.edu/en/contributions/view/3423
Authors: Emily Moore, Kathy Perkins, Trish Loeblein, Courtney Fadley
After reading the article, “4 tips for moving boxes and heavy furniture,” by K.C Roads,
Joe thinks he is ready to move out of his apartment. He decides to start with his biggest furniture,
7
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 3- Forces
a cabinet. He begins by just looking at it. (Scene 1) He then begins pushing on the cabinet across
the wooden floor. At first, the cabinet does not move. (Scene 2) Then the cabinet begins to slide.
(Scene 3)
Scene 1:
Joe not pushing
Scene 2:
Joe pushing but cabinet not
moving
Scene 3:
Joe pushing and cabinet
moving
1.
Use words to describe all the forces are acting on the cabinet for each scene.
Scene 1:
Joe not pushing
Scene 2:
Joe pushing but cabinet not
moving
Scene 3:
Joe pushing and cabinet
moving
2.
Why do you think the file cabinet moves in scene 3 but not in scene 1 or 2?
8
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 3- Forces
3. Draw and label the force arrows acting on the cabinet in each scene:
Scene 1:
Joe not pushing
Scene 2:
Joe pushing but cabinet not
moving
Scene 3:
Joe pushing and cabinet
moving
4. If Joe’s apartment floor was covered with ice, how would the motion of the cabinet change,
justify your answer?
5. If Joe’s apartment floor was covered with carpet, how would the motion of the cabinet
change, justify your answer?
9
Grade 8 Science- Assessment 1
Student Pages
LAUSD/2014-2015
Item 3- Forces
Scene 4: Joe pushing and cabinet moving 200 Nà ß 100N 40
6. Calculate the net force in scene 4. Determine if the forces are balanced or unbalanced? Describe the change in motion of the file cabinet. 7. Joe decides to re-­‐read the article. He wonders why the article would mention shoes and how it relates to friction. Explain to Joe why shoes would matter and how they are related to friction. 8. Use your science knowledge to analyze why wheels and dollies are helpful in the moving process. 10