"Today is an exciting day. We are going to examine cow eyes in order to better understand our own eyes," said Lincoln Elementary School teacher Laura Burstrom to second-graders in Mary Cook's class. "A cow eye is very similar to a human eye. Since we have been studying the parts of the eye during health, we thought it would be so interesting to dissect a cow eye. Does anyone know what the colored part is called on the eye?"
"The iris," said a student.
"That's right, you know the iris controls the amount of light that enters into the eye. Human irises are all different colors, but look at the cow eye, it's blue because all cow irises are blue."
Lincoln Elementary School second-grade students Collin Brown and Jayden Elifritz look at a newspaper through the lens from a cow’s eye in Mary Cook’s class.
Burstrom demonstrated, with the help of parent volunteers, how to find the different parts on the eye and what to look for when examining the cow eye. She then showed students how to dissect the cow's eye to be able to discover what was inside. Students searched for the eyelid, eyelash, iris, retina, sclera (or white part of the eye), vitreous body (transparent, colorless, gelatinous mass that fills the space between the lens and the retina lining), optic nerve, tear glands and lens. In one activity, students enjoyed placing the lens on a newspaper page to see how the cow eye lens actually magnified the words. The cow eye dissection was the culminating activity for a health unit on the five senses.
"It was so cool because I got to turn the cow eye inside out and see the retina, which looked like the colors of a seashell," said second grader Melody Snyder-Pratt. "We saw a fake, plastic eye during class but to actually see, feel and touch the real thing helped me learn about the eye better. Instead of our teacher just telling us about the lens, we actually got to see one."
Second-graders in Burstrom, Mary Cook and Matthew Langworthy's classes participated in a "Five Senses" unit. Students studied: taste, touch, smell, hearing and sight. They also completed a variety of experiments that included mapping the taste buds on their tongues and identifying a variety of smells. Students learned to "read" the Braille alphabet and wrote their names in Braille by gluing split peas to form the correct letters.
"As teachers, we try to create hands-on situations where students can live what they have learned," said Mrs. Cook. "The cow-eye dissection was a wonderful opportunity for students to see the actual parts of the eye. My goal is to let students experience, at an early age, what they will be doing in their middle school and high school science classes. This will provide them with background experience that they can draw upon in future. It is one of the highlights of their second grade experience."
The dissection is possible through the generous donation of cow eyes by Stevens Brothers in Panama.