Learn how to see microbes with your phone, in this episode of Gross Science from NOVA. You will need a smartphone, a laser pointer, poster tack, a piece of white paper, clear plastic packaging, a flashlight, and some water from a puddle. Take the lens out of the laser pointer and place the poster tack around the lens of the phone. Then, attach the laser pointer lens to the camera on your phone, with the convex side facing outward, and smooth out the poster tack. Cut two small strips of plastic to create a microscope slide, and place a droplet of water from a puddle between the strips. Place the slide on the white paper on top of a flashlight. Focus your DIY phone microscope, and zoom in on the sample until you see organisms. This resource is part of the NOVA: Gross Science Collection.