Unit 1: What Is Science? Lesson 1 The Scientific Method 2 Tools of Science 3 Fields of Science Unit 2: Life Science Lesson 4 Cells 5 Classification 6 Vertebrates and Invertebrates 7 Animal Classes 8 Warm-blooded and Cold-blooded 9 Plant Structure and Function 10 Photosynthesis 11 Seed Plant Reprod uction 12 Genetics 13 Human Reproduction 14 Human Body Structure 15 Nerves and Senses 16 Energy Systems 17 Ecosystems 18 Food Chains Unit 3: Physical Science lesson 19 Properties of Matter 20 States of Matter 21 Energy 22 Change in Matter 23 Forces 24 Motion and Work 25 Simple Machines 26 Heat and Temperature 27 light 28 Sound 29 Electricity 30 Magnetism 31 Energy Resources Unit 4: Earth Science Lesson 32 The Earth 33 The Earth's Features 34 Plate Tectonics 35 Rocks and Minerals 36 Weathering and Erosion 37 The Atmosphere 38 The Water Cycle 39 Weather 40 Seasons and Climate 41 Fossils 42 Geological Time 43 Oceans 44 Astronomy Glossary