7th Grade Life Science Curriculum Unit 2: Cell Biology Microscope Use Lesson 3: How Big Is It? Objectives: Students will learn how to use a clear plastic metric ruler to measure very small objects under the microscope. Students will measure the diameter of the "field of view" on the microscopes that they are using. Students will be able to draw the actual size of the field of view once they have practiced measuring with a plastic metric ruler. Key Questions: What is the function of each part of the microscope? What do you notice when you look at something with a microscope? How can you measure the size of an object under the microscope? Overview: It is difficult to judge what size an object is when using a microscope. In this activity, students will have the opportunity to investigate how to use a metric ruler to make rough measurement of the "field of view" of her/his microscope. By doing so, objects that are observed in future microscopic investigations can then be measured. Time Required: 1 class session Materials: compound microscope, clear plastic metric ruler (made from transparency ­ see 7th Grade Life Science Curriculum binder), paper and pen or pencil Procedure: See "What to Do" section in The Microscope Book, pages 20-22, ahead of time in order to provide appropriate instructions and data sheet. Assessments: Students make measurements of teacher-selected objects, using a clear plastic metric ruler, microscope, and various objects. Homework: Students will create a list of 10 objects that would fit in the "field of view" of their microscopes and draw to scale the how these objects would appear under their microscopes. OUSD Science Content Standards (State of California Science Content Standards): Investigation and Experimentation 1a, 1d References: Prentice Hall - Focus On Life Science textbook The Microscope Book Table of Contents Microscope Use (2 weeks) Lesson 1 Cartwheels (1 day) Water Lenses Lesson 2 The Compound Microscope (4+ days) My Microscope Study Sheet Microscope Rules for a Reason Microscope License Lesson 3 How Big Is It? (1 days) Lesson 4 Give Me An "e" (1-2 days) Fake or Counterfeit? Lesson 5 Sew Long (1 days) Lesson 6 Sounds Fishy to Me (1 days) Lab Helper (Slide Organize) Cell Structure (2 weeks) Lesson 7 Water, Water Everywhere (2 days) How to Label Microscope Diagrams Lesson 8 Greensleeves (1 day) Lesson 9 Onion Rings (1 day) Lesson 10 Don't Be Cheeky (3+ days) Cell Project Metaphors: More Cell Project Practice Cell Processes (1 week) Lesson 11 Diffusion (2 day) Lab Handout ­ Screen Play Lesson 12 Mitosis (2 days) Curriculum Resources Teaching Cartoon Project (Assessment Strategy) Learning Logs and Journaling Show Don't Tell!