Providing a history of the microscope's development gives students an understanding of the usefulness of this scientific tool. Explain that before the microscope was invented, scientists did not conclusively know of the existence of bacteria and viruses. The discoveries made by using microscopes have advanced science by leaps and bounds.
While most classes will use standard compound microscopes, you should teach your students about the different types of microscopes available today, including scanning electron and transmission electron microscopes. Explain how they are used and show photos to give your students a full understanding of the scope of microscopes.
The typical microscopes used in classrooms can be quite expensive. Schools must purchase enough of them for every student in a class, or at least every pair of students. Before allowing students to handle classroom microscopes, it is important to teach them how to handle them properly. Explain and demonstrate the proper way to pick up the microscopes, how to plug them in and unplug them as well as how to store them. Assign each student to a specific microscope so you can determine which students are not caring for their microscopes properly. Also teach your students how to adjust the stage. Make sure they understand that only the oil-emersion lens should actually touch the slide.
Teach your students the proper way to load a slide as well as how to start at the lowest magnification and work up to higher magnifications until you can see what it is you are looking for. Show them how to adjust the eyepieces. Have them practice looking through an already focused microscope with both eyes to get used to it. Demonstrate how to move the microscope's stage left and right as well as forward and back so students can review entire slides once they begin hands-on work. Once you are confident that your fifth-grade students know the proper handling and focusing techniques, distribute prepared slides and have them practice their newfound skills.