The 100 Things I Need to Know in Science for 5th Grade
Earth & Space Sciences
1. Stars are like our sun, some are smaller and some are larger, but so far away that they look like points of light.
2. Stars release energy in the form of heat and light.
3. Stars use nuclear fusion to produce heat and light.
4. In a star nuclear fusion occurs when two hydrogen atoms fuse (join together) to form one helium atom.
5. Our sun is a medium sized star.
6. A solar system contains a star(s), planets, moons, asteroids, and comets.
7. Period of revolution is when one object travels around another object. For a planet, a revolution is one year.
8. Period of rotation is one spin of the axis.
9. Our moon revolves around the earth. One complete revolution of our moon takes about a month.
10. Earth’s moon does not produce its own light. It reflects the light from our sun.
11. As the moon revolves around the earth, some parts of the moon are lit while others are not. We call these phases of the moon.
12. The axis is an imaginary line that passes through the Earth’s center at its North and South Poles.
13. It takes the Earth about 24 hours to rotate once on its axis. This causes night and day. One Earth day equals 24 hours.
14. The universe contains many galaxies. Each galaxy contains many solar systems.
15. It takes the Earth 365.25 days to revolve once around the sun. This equals one earth year.
16. The Earth’s axis is tilted about 23 degrees.
17. The seasons are caused by the relationship of the tilt of the Earth’s axis to its position as it revolves around the sun.
18. The Earth is a sphere.
19. The Earth has an elliptical orbit around the sun.
20. The Earth is mostly a water planet. Three-fourths of the Earth’s surface is covered with water – some of it frozen.
21. The Earth is surrounded by a thin layer of air which is our atmosphere.
22. The Earth is the only place we know of that has life.
Life Science
23. A food chain is the movement of energy from one organism to another in an ecosystem.
24. A food web is all the food chains in an ecosystem.
25. An ecosystem is a community of organisms and its physical environment together.
26. An ecosystem is made up of living (biotic) and non-living (abiotic) parts.
27. Herbivores are animals that eat only plants.
28. Carnivores are animals that eat only other animals.
29. Omnivores are animals that eat both plants and animals.
30. Insectivores are animals that eat only insects.
31. A consumer is an animal that eats plants or other animals as food.
32. A decomposer is an organism such as fungi, bacteria, or insects (FBI) that gets energy by feeding on the bodies of dead plants and animals.
33. Producers are green plants that turn the sun’s energy into food through a process called photosynthesis.
34. An individual is a single organism in an environment.
35. During photosynthesis, green plants take in carbon dioxide and sunlight. Chlorophyll, a coloring material, helps plants use light energy to produce sugars. Oxygen is released by the plant as a waste product.
36. A population is all the individuals of the same kind living in the same environment.
37. A community is all the populations of organisms living together in an environment.
38. A habitat is a place in an ecosystem where a population lives.
39. An ecosystem can only provide food, water, and shelter for a limited number of organisms. This is called the carrying capacity.
40. When gases produced by burning fossil fuels are mixed with water vapor in the air, acid rain is produced.
41. Natural resources can be conserved by reducing, reusing, or recycling them.
42. Ecosystems can be positively or negatively changed by nature or by humans.
43. Humans can negatively impact an environment by over hunting, cutting down forests, polluting, or by introducing non-native species.
44. Humans can positively impact an environment through planting trees and creating laws to protect organisms.
45. Trees, water, wildlife, and air are renewable resources that can be used again and again.
46. Renewable energy resources do not run out. These include wind power, water power, geothermal, and solar energy.
47. Nonrenewable resources are limited and cannot be replaced as quickly as they are used.
48. Fossil fuels (coal, oil, natural gas) are nonrenewable energy resources.
49. Nonrenewable resources can be extended through reducing, reusing, and recycling but cannot be extended indefinitely.
Physical Science
50. Heat is a form of energy that causes particles to move.
51. Cold is the absence of heat.
52. Heat always moves from warmer objects to cooler objects until they each have the same temperature.
53. Temperature is a measurement of the average speed of the moving particles within a substance.
54. Conduction is the transfer of heat through a substance by direct contact of the particles.
55. Convection is the transfer of heat through liquids or gases by currents of thermal energy.
56. Radiation is the transfer of heat through waves.
57. Zero degrees Celsius is the freezing point of water. One hundred degrees Celsius is the boiling point of water.
58. Thirty-two degrees Fahrenheit is the freezing point of water. Two hundred twelve degrees Fahrenheit is the boiling point of water.
59. Negative 459.65 degrees Fahrenheit is absolute zero (lowest possible temperature). All particles stop moving. All thermal energy stops.
60. Materials that transfer heat easily are called conductors.
61. Materials that don’t transfer heat easily are called insulators.
62. Heating causes most materials to expand. Cooling causes them to contract.
63. A substance usually exists in one of the three states: solid, liquid, or a gas depending on the motion of its particles. Fast – gas, medium – liquid, slow – solid.
64. A substance will change its state when its heat energy changes. Solid to liquid; add heat. Liquid to solid; take away heat.
65. Freezing point is the temperature at which a substance changes from a liquid to a solid. Melting point is the same temperature as the freezing point, but solid changes to a liquid.
66. Evaporation occurs when a substance changes from a liquid to a gas. Condensation occurs when a substance changes from a gas to a liquid.
67. Electric current is the flow of electrons and their energy from one place to another.
68. An electric circuit is a pathway that allows electric current to flow.
69. An open circuit does not allow electrons to flow.
70. A closed circuit does allow electric current to flow.
71. A conductor is any material that allows electric current to easily pass through it.
72. An insulator is any material that does not allow electric current to pass through it.
73. Electric current in a circuit can produce thermal, sound, and light energy as well as magnetic forces.
74. Light is the visible part of the electromagnetic spectrum (ROY G BIV – red, orange, yellow, green, blue, indigo, violet).
75. All light energy travels in waves.
76. When visible light hits a smooth, shiny surface, it is reflected (bounced off). The incoming angle of light is equal to the outgoing angle.
77. Refraction is when visible light passes through a transparent object, slows down and bends.
78. The speed of light is 186,000 miles per second in space.
79. A green object appears green to our eyes because all the colors except green are absorbed into the object. Only the green is reflected.
80. A white object reflects all the visible light and absorbs none.
81. A black object absorbs all the visible light and reflects none.
82. All sounds start with a vibrating object.
83. Sounds travel in waves.
84. When sounds pass through objects they cause the object to vibrate.
85. Sounds will not travel through a vacuum (a place with no air).
86. More vibrations per second produce a higher pitch. Fewer vibrations per second produce a lower pitch.
87. Sound travels through different objects at different speeds. Air = 1100 feet per second, steel = 16,400 feet per second.
88. Sound that is reflected off an object is called an echo.
Scientific Inquiry
89. The scientific method is a series of steps scientists use to search for an answer to a clear, well-defined question.
90. A hypothesis is a possible answer to a question based on what you have learned or observed.
91. A procedure is a step-by-step plan of an experiment that shows how you will test your hypothesis.
92. Materials are the items required for an experiment.
93. Variables are anything that can change in an experiment.
94. Data is information.
95. Data you collect using your senses is called a qualitative observation.
96. Data you collect through measuring is called a quantitative observation.
97. A conclusion should state whether your hypothesis is correct or incorrect. Your conclusion must be supported by the data you collect.
Science Safety
98. Never eat or drink anything during a science lab.
99. Never touch, taste, or smell chemicals.
100. Report all accidents to your teacher at once.