photo by Michelle Gill

The 5th-grade science curriculum in District 97 focuses on the various systems in the
body. But what if you could have some of those systems actually brought into the classroom to

Dr. David Hines, M.D., a veteran of OPEF’s Global Village* program and a specialist in
infectious diseases at Rush Medical Center, has done just that. In the past couple of months he
brought the skeletal system to Ms. Yigzaw’s classes at Holmes in the form of human and animal
bones, and the cardiovascular system in the form of a sheep’s heart.

During his first visit in April, Dr. Hines showed deer and human spines and asked the students
to look for the differences. The students could see that the vertebrae on a deer are all about
the same size, while those on a human get larger further down the spine. As one student noted
this is “because deer have 4 legs and their spine is horizontal,” so weight is evenly distributed.
Humans, however, are upright and the lower spine has more weight to carry.

Another student asked “Is it fake?” Dr. Hines told the kids, “I only bring real stuff here.” An
avid bird-watcher, he said he finds deer and other animal skeletons while bird-watching in
Thatcher Woods. Jack W. enjoyed carry the human spine up and down the rows to show his
classmates. The 5th graders were captivated by the good-humored Dr. Hines.

Dr. Hines also showed students a real human skull. He asked them “Why do skulls have sutures
[the seam down the top of the skull]?” One student responded “because the skull isn’t all one
bone.” Students went on to piece together the clues of how our skulls are formed and why they
are formed that way. The kids were able to examine various specimens of animal skulls as well
as delicate fish cartilage.

Dr. Hines also showed the 5th graders an x-ray, holding it up against the light of the window.
He explained that x-rays work because the calcium in our bones causes the x-rays to bounce off.
The light can’t get through, so the shapes of the bones show up–a bit like a shadow in the sun.

On a subsequent visit from Dr. Hines in May, the 5th graders got up close and personal
with sheep hearts, as they dissected them in small groups. Savannah S. said, “It is nasty but
educational.” To demonstrate she noted, “If you put a toothpick [into one of the blood vessels]
and move it, it looks like the heart is working!”

Ryan M. agreed: “It’s nasty but it’s a good experience. It’s not just the computer, but here in real
life, so you can see how it works.”

Ms. Yigzaw also emphasized this advantage. “It’s nice for them to see it up close. We have a
model [of the heart], but this is better. It’s really nice to have Dr. Hines in here. He obviously
really knows what he is talking about.”

See a slideshow of photos by Holmes parent Michelle Gill.


* The program is now named “Science Alliance”