Our eyesight is inherently limited. Through the years, we have evolved the ability to find predators and prey at great distances, and our eyes have evolved to help us define food and water. When it comes to seeing especially small objects, however, our eyes are not up to the task. Fortunately, student compound microscopes can open up a world that we cannot see with the unaided eye, and many of the findings in this world can be truly astounding. Here is an idea for an experiment teachers and parents can share with children that will open their eyes to the world of microscopic creatures living all around us.
First, those helping children perform this experiment want to ensure that they have a slide capable of holding water. Further, a dropper is needed to transfer water from a container to the slide. Once these tools been acquired, parents or teachers can go to various locations to collect water samples. If possible, it might be fun to bring children along for this part of the experiment. Tap water and bottled water should be used, but pond water, ocean water and water from a muddy area should be included if they are available. Place the samples into a container and label them.
After teaching the participants how to use a microscope, instruct them to place various water samples on to a slide and place it under the microphone. Upon focusing on the sample, most children will be amazed; there is an entire world of creatures that live in the water, and the sheer number of creatures can be staggering. We often think of water is a static, unchanging substance, but the reality is much more interesting. Have the children draw what they see, and perform some research after this is done to identify which creatures they of noted.
Euglenas are often found in water samples, and it is of interest that these creatures form a link between plains and animals. Algae is common as well, but algae can be difficult to distinguish from protozoa. Amoebas can also be found, and the children may be interested to hear that amoebas survived by eating other microscopic creatures found in the water. Especially lucky students may be able to see an amoeba eating some unfortunate creature. Identification can be a bit of a challenge, but the Internet has made it possible to establish which creatures students are seeing.
Hayley is an amateur scientist, author and blogger residing in Portland Oregon. She uses student compound microscopes to tutor High School science students in her free time. Interested in more fun and fascinating science projects you can perform at home? Visit chemistry.about.com.