Beautiful examples of fractals in nature can be found with a simple Google Image Search. To get more specific, search for fractal snowflakes, fractal coastlines, fractal tree branches, or fractal river systems.
To help students get some practice identifying fractals in nature, we took them on a hike in a nearby park. It was pouring, but the students remained in good spirits. Temperate rainforests are always good for ferns, moss, and intricate tree bark—all of which are excellent sources of fractals.
After our lengthy discussions of fractals and chaos theory, it was time to focus on fractals in nature. The students each chose a biome to research, and their report must include information on animals, plants, natural cycles, and abiotic factors. Fractals can be found in all of those things. For this art piece, each student chose a natural fractal specific to their biome.
The final art piece for this project is framed etched glass. An eclectic selection of frames was acquired from various thrift stores around Portland, and each student spray-painted their frame the same shade of flat black. I created the example piece below using an image of leaf veins (while my Christmas tree was still decorated).