UNIT 3: Force, Motion, and Energy ..............................108
Lesson 1: Force and Motion ..................................................................108
Lesson 2: Electrical Energy ...................................................................122
Lesson 3: Reflection and Refraction of Light .........................................131
UNIT 4: Earth and Space, Part 1 ..................................144
Lesson 1: The Water Cycle ....................................................................144
Lesson 2: The Sun, Earth, and Moon ....................................................156
Lesson 3: The Rotation of Earth ............................................................166
UNIT 5: Earth and Space, Part 2 ..................................180
Lesson 1: Earth’s Changing Surface .....................................................180
Lesson 2: Sedimentary Rock .................................................................196
Lesson 3: Alternative Energy Resources ...............................................204
Lesson 4: Past Living Organisms ..........................................................214
UNIT 6: Organisms and Environments, Part 1 .............228
Lesson 1: Interactions of Organisms in Their Environments ................228
Lesson 2: Food Chains and Food Webs ................................................237
Lesson 3: A Balanced Environment .......................................................254
