You have a microscope--now what? With the directions in this Teaching Tip you can get started right away making your own microscope slides.
- Cork Cells
- How to Make a Smear of Cheek Cells
- Looking at Root and Stem Sections
- Leaf Cells
How to Make Simple Microscope Slides
- Making Simple Slides
- How to Use the Microscope
- Other Simple Microscope Slide Ideas
Learn how to make temporary mounts of specimens and view them with your microscope. Below are a few ideas for studying different types of cells found in items that you probably already have around your house.
In the late 1600s, a scientist named Robert Hooke looked through his microscope at a thin slice of cork. He noticed that the dead wood was made up of many tiny compartments, and upon further observation Hooke named these empty compartments cells. It was later known that the cells in cork are only empty because the living matter that once occupied them has died and left behind tiny pockets of air. You can take a closer look at the cells, also called lenticels, of a piece of cork by following these instructions.
Materials Needed:
- a small cork
- plain glass microscope slide
- slide cover slip
- sharp knife or razor blade
- water
How to make the microscope slide:
Carefully cut a very thin slice of cork using a razor blade or sharp 
knife (the thinner the slice, the easier it will be to view with your microscope). To make a wet mount of the cork, put one drop of water in the center of a plain glass slide - the water droplet should be larger than the slice of cork. Gently set the slice of cork on top of the drop of water (tweezers might be helpful for this). If you are not able to cut a thin enough slice of the whole diameter of the cork, a smaller section will work.
knife (the thinner the slice, the easier it will be to view with your microscope). To make a wet mount of the cork, put one drop of water in the center of a plain glass slide - the water droplet should be larger than the slice of cork. Gently set the slice of cork on top of the drop of water (tweezers might be helpful for this). If you are not able to cut a thin enough slice of the whole diameter of the cork, a smaller section will work.
Take one cover slip and hold it at an angle to the slide so that 
one edge of it touches the water droplet on the surface of the slide. Then, being careful not to move the cork around, lower the cover slip without trapping any air bubbles beneath it. The water should form a seal around the cork. Use the corner of a paper towel to blot up any excess water at the edges of the coverslip. To keep the slide from drying out, you can make a seal of petroleum jelly around the cover slip with a toothpick. Begin with the lowest-power objective to view your slide. Then switch to a higher power objective to see more detail. Use this same wet mount method for the other cell specimens listed below.
one edge of it touches the water droplet on the surface of the slide. Then, being careful not to move the cork around, lower the cover slip without trapping any air bubbles beneath it. The water should form a seal around the cork. Use the corner of a paper towel to blot up any excess water at the edges of the coverslip. To keep the slide from drying out, you can make a seal of petroleum jelly around the cover slip with a toothpick. Begin with the lowest-power objective to view your slide. Then switch to a higher power objective to see more detail. Use this same wet mount method for the other cell specimens listed below.
You can even check out cells from your own body! The cells on the inside of your cheek are called Squamous Epithelium cells and can be easily viewed with a compound microscope.
Materials Needed:
- toothpick (flat ones work best)
- plain glass microscope slide
- slide cover slip
- methylene blue
How to make the microscope slide:
To make a cheek smear, take a clean toothpick and gently scrape the inside of your cheek. Then wipe that part of the toothpick in the center of your slide. Hold the coverslip with one end flush on the slide and gently wipe the edge of the coverslip along the middle of the slide's surface. This will smear the cells along the slide, making a layer thin enough to view clearly. Let the smear air dry.
Once your smear is dry, add a drop of methylene blue stain to the center of the smear so you will be able to see the cells more clearly. Gently set a coverslip over the smear and scan your slide under low power to locate the cells, then observe them more closely under high power.
Vegetables are a great way to learn about plants. Did you know that carrots are actually roots, and celery stalks are stems?
Materials Needed:
- celery stalk (stem)
- a carrot (root)
- plain glass microscope slides
- slide cover slips
- water
How to make the microscope slide:
Cut a few extremely thin slices out of the middle of the carrot, and some from the middle of the celery stalk. Make a wet mount of the best slice from each vegetable and view them one at a time using your microscope's 4x objective. Compare and contrast what you see in each one, then switch to the 10x objective to look a little more closely. To see details of the amazing structure of plants, use the 40x objective and scan each slide, carefully observing all of the parts and different cells.
Learn even more about plants by studying different sections of real leaves.
Materials Needed:
- a fresh leaf specimen (use one without many holes or blemishes)
- plain glass microscope slide
- slide cover slip
- sharp knife or razor blade
- water
How to make the microscope slide:
Before you begin, make sure the leaf is clean and dry. Lay it out flat on your working surface and slice about a 1'' section crosswise out of the center using a sharp knife. Then, starting at one of the short ends (the edges that you did not cut), tightly roll the leaf section. Carefully make several very thin slices off one end of the roll with a razor blade or knife. The slices should look almost transparent. The cells surrounding the central vein of the leaf are what you will want to look at; depending on the size of the leaf, you might have to cut the slice again so that the central part is the part you will actually see on your slide. Make a wet mount on a plain slide with the inner part of the leaf section facing up (so the inner cells are visible). Look at the slide with the 10x objective to see the general structure, and higher power to see details of cells.
A tool called a microtome is extremely helpful for preparing specimens for slide mounting. A microtome allows you to expose a small amount of the specimen at a time and cut it off against a solid edge using a very sharp razor blade type knife.
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