1. Written by Chris Jackson, Ed.D.
GRADE 8 STAAR SCIENCE REVIEW
Written by Chris Jackson, Ed.D.
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2. Grade 8 STAAR Science Review
All clipart and images used in this review are either created by Hedgehog Learning, found in public domain, or used with permission from iStockphoto, iClipart, Microsoft, or 123RF
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3. STAAR Review DAY 1 MATTER AND ENERGY
TEKS 8.5A (R), 8.5B (R), 7.5C (S), 7.6A (S), 7.6B (S)
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4. Structure of Atoms Nucleus of the Atom - Contains Protons and Neutrons
Protons, Neutrons, and Electrons
Nucleus of the Atom
- Contains Protons and Neutrons
Electron Cloud of the Atom
- Contains Electrons
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5. Protons, Neutrons, and Electrons
Take a minute to fill in the table below on a piece of paper…
Protons
Neutrons
Electrons
Mass of Particle
(1, 0)
Charge of Particle
(-1, 0, +1)
Location of Particle
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6. Protons, Neutrons, and Electrons
Is this what you came up with?
Protons
Neutrons
Electrons
Mass of Particle
(1, 0) 1
Charge of Particle
(-1, 0, +1) +1 -1
Location of Particle
Nucleus
Orbitals or Electron Cloud
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7. Makeup of an Element
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The ATOMIC NUMBER indicates the number of PROTONS in an ELEMENT
The ATOMIC MASS (rounded) indicates the number of PROTONS plus NEUTRONS
Only Oxygen has 8 protons, which makes it a unique element.
To find the number of neutrons, subtract the atomic number from the atomic mass:
16 – 8 = 8
Electrons are normally equal to the number of protons if the charge of the atom is zero.

8. Gaining (or Losing) a Charge!
Element + Element = Compound
Most elements will either gain or lose valence electrons and become charged.
Nonmetals (right side of periodic table) typically gain electrons and are negatively charged.
Metals (left side of the periodic table) typically lose electrons and are positively charged
Because metals and nonmetals are oppositely charged, these individual elements will combine to form compounds.
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9. Gaining (or Losing) a Charge!
= VALENCE ELECTRON
12 P
8 P Mg O
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10. Gaining (or Losing) a Charge!
= VALENCE ELECTRON
Lose 2 Electrons
+2 Charge
Gain 2 Electrons
-2 Charge
12 P
8 P Mg O
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11. Reactivity
The number of valence electrons will determine how reactive an element will be.
If an element has valence electrons to gain or lose, it will be very reactive.
If an element has all eight valence electrons, it is considered to be non-reactive.
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12. Chemical and Physical Changes in the Digestive System
Identify examples of physical and chemical changes that occur at each of these points. A B C
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13. Energy and Food Webs
On a piece of paper, diagram the flow of energy through these organisms.
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14. Organic Compounds CARBON
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Organic Compounds are compounds containing carbon.
Organic compounds are the building blocks of life, including substances like fats, sugars, and protein.
Fossil fuels are also organic compounds.
Can you identify any other carbon-containing compounds?
Hydrogen
Oxygen
Phosphorus
CARBON
Nitrogen
Sulfur

15. STAAR Review DAY 2 MATTER AND ENERGY
TEKS 8.5C (R), 8.5D (R), 6.5C (S), 6.6A (S), 6.6B (S)
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16. Periodic Table
GROUPS
PERIODS
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17. Periodic Table METALS Conducts heat Conducts electricity Solid
Alkali and Alkaline Metals
Transition Metals
Conducts heat
Conducts electricity
Solid
Lustrous
Malleable
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18. Periodic Table METALLOIDS Semiconductors of electricity
Properties of metals and nonmetals
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19. Periodic Table NONMETALS Gas or Liquid
Poor conductors of electricity and heat
Reactive with metals
Noble gases (green column) are unreactive.
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20. Chemical Reactions Reactants Products 2AB + C2  2CB + 2A
Elements and Compounds
Reactants
Products
2AB + C2  2CB + 2A
Coefficient Subscript Compound Element
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21. STAAR Review DAY 3 MATTER AND ENERGY TEKS 8.5E (R), 8.5F (S)
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22. Chemical Changes CHEMICAL CHANGE
a change when a new substance is formed from the reaction between two or more different substances
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23. Physical Changes PHYSICAL CHANGE
a change in the temperature, state of matter, shape, density, or any other observable characteristic of a substance
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24. Law of Conservation of Mass
Mass of Reactants = Mass of Products
Before
After
How does the mass of the egg change before and after cooking? Do the physical and chemical changes affect the mass?
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25. Balancing of Chemical Equations
Law of Conservation of Mass in Chemical Reactions
H2 + O2  H2O
On a piece of paper, balance this reaction between hydrogen and oxygen gas.
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26. Balancing of Chemical Equations
Law of Conservation of Mass in Chemical Reactions
Was this your answer?
2H2 + O2  2H2O
4 atoms of Hydrogen on both sides
2 atoms of Oxygen on both sides
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27. STAAR Review DAY 4 FORCE, MOTION, AND ENERGY
TEKS 8.6A (R), 8.6B (S), 6.8C (S), 6.7D (S)
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28. Forces Consider the forces acting on these books.
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Gravity pulling downward
Consider the forces acting on these books.
Are the books moving?
Are the forces balanced or unbalanced?
Air pressure
Air pressure
Table pushing upward

29. Forces
Balanced Forces - occurs when multiple forces acting on an objects does not cause an object to change its speed
Unbalanced Forces - occurs when multiple forces acting on an object causes the object to increase or decrease speed
Identify if these items are examples of
BALANCED or UNBALANCED forces.
Constant speed
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30. Balanced or Unbalanced
What is the net force acting on these objects?
Will these objects change speed?
2 N
15 N
3 N
1 N
25 N
2 N
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31. Speed, Velocity, and Acceleration
Speed – the distance an object travels in a certain amount of time
Velocity – the speed and direction of an object
Acceleration – a change in velocity
An airplane flies from Dallas to Boston, a distance of 1500 miles, in 4 hours. Describe the flight of the airplane in terms of average speed and velocity. When does the airplane accelerate?
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32. STAAR Review DAY 5 FORCE, MOTION, AND ENERGY
TEKS 8.6C (R), 7.7A (S), 6.8A (S), 6.9C (S)
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33. Newton’s 3 Laws of Motion
#1 – an object will only change speed if acted on by an unbalanced force - Law of Inertia
#2 – the acceleration of an object is related to the its mass and the force acting on it
F=ma
#3 – every action has an equal and opposite reaction
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34. Which Law of Motion?
Identify which law of motion is being represented.
A moving red billiard ball hits the side bumper on the table and bounces backward at nearly the same speed.
An airbag inflates to help cushion to rapid deceleration of the people inside the car during an accident.
A powerful rocket engine producing more force is used on a more massive rocket to produce the same acceleration.
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35. Energy Highest Potential Energy Highest Kinetic Energy
The energy that results due to an object’s position
Kinetic Energy
The energy derived from an object’s motion
When is kinetic energy converted to potential energy during a roller coaster ride?
Highest Potential Energy
Highest Kinetic Energy
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36. Work – the energy needed to move an object over a certain distance
This is so much WORK!
Work – the energy needed to move an object over a certain distance
5 kg
The woman had to pick up a box with a mass of 5 kg and lift it a distance of 2 meters.
How much work did she do?
Would the amount of work change if she used a ramp to help her?
2 m
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37. Energy Conversions
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Name the energy conversions in each of the pictures to the right using the following terms:
Solar Energy
Mechanical Energy
Sound Energy
Chemical Energy
Electrical Energy
Light Energy

38. STAAR Review DAY 6 EARTH AND SPACE
TEKS 8.7A (R), 8.7B (R), 8.7C (S), 6.11B (S)
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39. Rotation of Earth NIGHT DAY
The Earth rotates once every 24 hours or 1 day.
The rotation of the Earth causes day and night since the side facing the Sun is always moving.
The rotation of the Earth does not cause seasonal changes.
Rotation of the earth
NIGHT
DAY
sunlight
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40. Revolution of the earth
Revolution of Earth
The Earth revolves around the Sun every 365 days or 1 year.
The Earth’s revolution causes the changes in the seasons due to the tilt of the Earth.
The revolution of the Earth does not cause day or night.
Revolution of the earth
SUMMER
WINTER
WINTER
SUMMER
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41. Phases of the Moon
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The Moon revolves around the Earth about once every month.
What phase of the Moon will occur about two weeks after a full moon?
What phase of the Moon will occur about one week after the first quarter?

42. Please understand the GRAVITY of the situation…
Mass = Gravity
Gravity is the force that holds the solar system together.
The mass (and thus gravity) of the Sun keeps all the planets orbiting around it.
The mass (and thus gravity) of the Earth keeps the Moon orbiting around it.
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43. Tidal Forces – Moon and Sun
The Moon has much greater affect on the Earth’s tides because it is closer to the Earth.
When the Moon, Sun, and Earth are aligned (new and full Moon), the tides are the greatest (Spring Tide)
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44. STAAR Review DAY 7 EARTH AND SPACE
TEKS 8.8A (R), 8.8B (S), 8.8C (S), 8.8D (S)
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45. We are just a speck…
If we were traveling at the speed of light, it would take us _________ to reach ________.
1 second
Moon
8 minutes
Sun
1 hour
Saturn
4.2 years
Nearest Star (Proxima Centauri)
6,500 years
Crab Nebulae
26,000 years
Center of the Milky Way
2,500,000 years
Nearest galaxy (Andromeda)
93,000,000,000 years
Other side of the universe
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46. Solar System
Our own personal star
Our solar system is extremely tiny compared to the Milky Way Galaxy.
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47. Stars
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The stars we see at night are located “nearby” in the Milky Way galaxy.
Stars in other galaxies are too far away for us to see them individually.
Stars have “life cycles” similar to plants and animals. Average stars, like our Sun, are born in nebulas and die as red giants.

48. Life Cycles of Stars
Models, like a Hertzsprung‐Russell diagram, show us how stars change over time.
Based on this diagram, what would you say about the age of our Sun compared to other stars on the main sequence?
Brighter
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Hotter Cooler

49. Galaxies
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Our galaxy, the Milky Way galaxy, is made up of BILLIONS of stars.
There are BILLIONS of galaxies in the universe.
Types of galaxies include:
Spiral galaxies
Barred spiral galaxies
Elliptical galaxies
Dwarf galaxies
Ring galaxies

50. STAAR Review DAY 8 EARTH AND SPACE
TEKS 8.9B (R), 8.9C (R), 8.9A (S), 8.10A (S), 8.10B (S), 8.10C (S), 7.8C (S)
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51. Plate Tectonics What do the orange dots represent?
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52. Crustal Features
Which of these two landscapes is hundreds of miles away from a crustal boundary?
Give a reason to support you answer.
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53. Plate Tectonics
At which number on the map are the following crustal features occurring?
Tall mountain range formed from one plate moving into another plate.
A mid-ocean ridge where two plates are separating.
Earthquakes where two plates are moving past each other. 3 1 2
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54. Erosion and Weathering
Constant reshaping of our planet
What features can you identify in this satellite picture?
What are the brown areas?
Where does this come from?
Where is it going?
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55. Weather Symbols
Identify these weather symbols and describe what they mean.
In which direction to high pressure systems rotate in Texas? Where is the world would they rotate the other direction?
What is responsible for all moving currents, both in the atmosphere and in the ocean? H L
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56. Hurricanes
Hurricanes occur in the Atlantic ocean during the summer and fall. Why do they occur during this time and not during the winter?
Where does the energy for hurricanes come from?
In which direction to hurricanes rotate in the Northern Hemisphere? Southern Hemisphere?
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57. STAAR Review DAY 9 ORGANISMS AND ENVIRONMENTS
TEKS 8.11A (R), 8.11B (R), 7.10B (S), 7.10C (S), 7.11C (S), 8.11D (S)
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58. Food Webs and Energy
In the food web to the left, what role does the Sun play?
Identify the producers, consumers, and decomposers.
How does the ant play a part in the food web?
What would happen to the snake population if the rabbits were over-hunted?
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59. Parasites
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A parasite is an organism that must get its energy from another organism.
Sometimes the relationship is mutually beneficial.
Sometimes one organisms causes the other harm.
Can you think of a parasite that benefits it host?
What about the mosquito in the picture?

60. Ecosystems Look at the ecosystem in the picture to the left.
Suppose a fire disturbed this area 10 years ago. How has ecological succession occurred since then.
How is competition for resources occurring in this ecosystem?
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61. Ecosystem
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In this ocean ecosystem, how are organisms are competing for:
Sunlight
Living space
Food
Oxygen

62. Natural Selection
How does natural selection explain why giraffe’s have long necks?
Why is biodiversity important to natural selection?
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63. STAAR Review DAY 10 ORGANISMS AND ENVIRONMENTS
TEKS 8.11C (R), 7.11A (S), 7.12B (S), 7.12D (S), 7.12F (S), 7.14B (S), 7.14C (S), 6.12D (S)
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64. Traits and Environmental Changes
Why did the environmental changes in the early 1900’s in England cause the “gray” peppered moth to decline, but the “black” peppered moth increased in population?
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65. Traits and Environmental Changes
Genetic trait for skin tone and skin cancer risk
People with a genetic trait for fair skin are more likely to get skin cancer during their lifetime.
Fairer-skin humans generally originated further away from the equator than darker-skin humans.
Explain how the environment influenced early human traits for skin tone.
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66. Dichotomous Keys
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Dichotomous keys help us to identify organisms based on their physical characteristics.
What is the dichotomous key in the picture used to identify?

67. Body Systems
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68. Reproduction Sexual Reproduction Requires male and female
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Sexual Reproduction
Requires male and female
Fewer offspring
Greater genetic variation
Asexual Reproduction
Requires only one parent
Many offspring
Less genetic variation
What are the advantages of sexual reproduction in fighting off certain illnesses over multiple generations?
Some plants can reproduce asexually.
Animals reproduce sexually and produce fewer offspring.

69. Parts of a Cell Parts of a Cell Looking at the diagram on the right:
Where is the genetic material contained?
Is this cell prokaryotic or eukaryotic?
Is this cell autotrophic or heterotrophic?
Would this cell be found in the animal kingdom?
Parts of a Cell
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70. Human Interaction with the Oceans
Building artificial reefs to replace those damaged by humans
Many coral reefs have been damaged or destroyed by human activity and pollution.
In an effort to restore destroyed reefs, scientists have created artificial reefs like the one in the picture.
What other ways have humans influenced the ocean habitat?
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71. Best wishes for success on the Grade 8 Science STAAR!
Written by Chris Jackson, Ed.D.
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