Lesson Plan One
Identifying the Macroinvertebrates
In this lesson students will try to identify the organisms in a sample of pond water.
They will record their findings.
- Make observations about the properties of an organism.
- Record data.
- Use language to clarify their observations.
- Summarize information.
- Shallow pans, such as dish pans, for each group
- Ladles, scoops, spoons, eyedroppers to use in transferring samples to smaller containers
- Small containers to separate the samples for study (e.g. baby food jars, petri dishes, ice cube trays,etc.)
- Hand lenses
- Macroinvertebrate Identification Sheet (Click here and print out)
- Paper or notebooks, pencils, crayons
- Optional: Field guides such as Pond Life ( a pocket Golden Guide)
- Optional: Microscopes, slides.
- Familiarize yourself with some of the organisms you might find in the sample. The guide sheet provided shows ten macroinvertebrates that are commonly found in pond water.
For this activity, do the following:
- Divide class into groups of 3 -5 students.
- Before the students take their own samples from the collected pond water, gather them around the large sample for an initial "gross examination."
- Ask them to share their observations. Tell them that it will be possible to identify most of the organisms in the sample using just a hand lens or the eye.
- Each group should take several samples (making sure that they dip into the container and don't just collect from the surface) and put it into their shallow pan. They will then have a large sample from which each student can collect smaller samples for study.
- After each group has collected a sample in the dish pan, each student should use an eyedropper or spoon to collect samples from the pans and separate them into smaller containers for closer examination.
- Distribute Macroinvertebrate Identification Sheet to each student.
- Students should observe, identify, and use the identification sheet to record the type and number of visible organisms found in each sample.
- Student should make notes about organisms that they cannot identify, using writing and pencil sketches.They should make as many observations as they can, including color, size, shape, way of moving, number of legs, etc..
- Remind students not to return their sample to the dish pan because the animals in it have already been counted.
- Give students time to browse through additional resources and see if they can identify specimens that are not on the list.
Note: If low powered microscopes are available, use the eyedroppers to place a specimen on a depression(concave) slide.