This activity was developed by NASA's Global Precipitation Measurement (GPM) team as an introductory experience to a series of lessons about water resources on Earth.

In this lesson, students investigate and identify various phytoplankton using images that were previously taken with a compound microscope.  Credit:  This lesson is modified from a lesson of the same name created by The Center for Microbial Oceanography: Research and Education&nbsp

This lesson is taken from NASA's Phytopia: Discovery of the Marine Ecosystem written in partnership with Bigelow Laboratory for Ocean Science with funding from the National Science Foundation.

In this activity, you will use an inexpensive spectrophotometer* to test how light at different visible wavelengths (blue, green, red) is transmitted, or absorbed, through four different colored water samples.

 Air, Water, Land, & Life: A Global Perspective