Third graders usually don’t take part in dissecting cow eyeballs as part of their science studies. But students in Melissa Clark’s class at Magnolia Elementary School aren’t a usual group.
As part of their unit on “animal adaptations” the third graders saw first hand the parts of the eye on Friday, March 2 as they carefully cut their way through the layers of the dissection project themselves.
The state science standards regarding animal adaptations, that Clark’s students are in the process of learning, includes learning about different structures, such as the eye, that help an animal grow, survive, and reproduce.
By the day of the dissection they had already spent about a week in the unit on eyeballs. Just prior to taking the first cut, they studied the eye’s main parts on paper – the pupil, iris, and sclera. Then the students looked into each other’s eyes to identify the parts. Next came the cow eyes, which were placed on a special cutting mat in front of each pair of students.
They were each told to “be a surgeon” as they performed the dissections and the student partners shared in the duties. They started by cutting away part of the connective tissue around the eyeball. Then they cut away the cornea with a scalpel. As they made their way into each layer of the eye, they regrouped at each step and planned their next cut before proceeding. The iris is behind the pupil, then there’s the lens, which one student said looked like a pearl in her hand. What about all that liquid? The students knew that the purpose of the liquid, the aqueous humor, is to help the eye keep its shape.
“I expected it was going to be like a full circle and that we’d cut it in half,” said student Allyson Bengtson, adding that she thought the dissection would be performed much differently.
Dissections of this type are usually performed by older students with more maturity, but the “ick” factor is still typically present. Oddly, there were none of the expected sounds of “eeewww” or “yuck” coming from this group of third graders.
“It helps, the younger they are,” Clark said. “They’re not squeamish. This group, particularly, is just really ready for that.”
The students eventually made their way to the back of the eye where they found the retina, which hold the cones and rods and helps us see color and shape. The students “ooohed” and “ahhhed” when they got to the retina and saw its mother-of-pearl-like iridescence.
“I never knew that it was going to be so beautiful on the inside,” Bengtson said. “…It was unusual. You’d think it’d be all yucky inside but it was like a pearl, it was all different colors.”
Bengtson did admit, however, that it made her feel weird to think her own eyes were somewhat similar.
“I thought it was actually a really fun experience,” added student Ava Merchant. “I thought it would be kind of gross when I first saw the eyeball, but I kind of got used to it. I thought it was really neat. I could have fun and learn a lot at the same time.”