When school started this year, Ms. Stephanie Groom of Douglas County's Renaissance Magnet Elementary School in Castle Rock told her combined third and fourth grade class they could have class pets. Days later Skyler Feldman, an eager member of this eager class, offered his older sister's pet hedgehog. Apparently Skyler's older sister and Skyler's parents were willing to make this sacrifice, the sacrifice of letting Harley the Hedgehog go, for the good of the class.

Harley and his big tank were quickly installed in the classroom. Students were intrigued. Hedgehogs are not as common as, say, hamsters or turtles. Most of the students, most adults, too, knew little about these intriguing, exotic creatures.

Harley fit right in. The children learned proper care under the guidance of their teacher. They also learned about hedgehog habitat, habits and diet, in keeping with the learn-by-doing educational philosophy of the school.

Last week children saw blood in Harley's tank. They alerted Ms. Stephanie and she did what any compassionate animal lover and insightful teacher would do. She sought the care of a veterinarian.

Money is tight in schools. It is virtually nonexistent when it comes to medical care for class pets. Nevertheless, Ms. Stephanie scooped Harley up and headed after school to nearby animal clinics in hopes of medical attention without dire financial consequences. The cost of Harley's care would likely come from her own funds.

Two veterinarians refused to treat Harley. Just as the outlook was turning grim, Ms. Stephanie was told by her third animal care facility they'd help, of course.

On the third try, Ms. Stephanie and Harley had the good fortune of landing on the doorstep of Dr. Deborah Colgin and her assistant, Kelly, at the Brooklyn Veterinary Clinic in Castle Rock ( www.brooklynvet.com). Dr. Colgin discovered the blood the students saw in Harley's tank had come from Harley's feet. Worse, the feet appeared to have been gnawed by Harley himself. The wise doctor asked Ms. Stephanie if Harley could have gotten an irritating substance on his feet. Ms. Stephanie quickly realized she might have unwittingly caused Harley's maladies with her recent careful cleaning of the inside of his tank with scented wipes. Dr. Colgin explained hedgehogs are highly sensitive to odors and the perfuming ingredient of the scented wipes, which Harley would have stepped in, would surely be enough to cause the little hedgehog to try to chew it off his own feet.

Bad feelings accompanied relief. The good news was Harley would be fine, and that good news was forwarded to worried families via Ms. Stephanie's weekly classroom newsletter.

Dr. Colgin kept Harley overnight. Treatment included x-rays, an injection and a week of medication for a total of $40. Ms. Stephanie taught an additional lesson in responsibility by asking students to cover the modest medical fee with a few dollars each, and a few dollars extra for a gift for Dr. Colgin and her staff as a show of appreciation.

Hedgehog lessons here are many. Pets make great tools in learning-by-doing. Innovative teachers teach in ways surprising, perhaps, even to themselves sometimes. Children with a creative teacher, such as Ms.Stephanie Groom, and the good fortune of encountering a community-minded business, such as Brooklyn Veterinary Clinic, have opportunities to expand their minds far beyond the classroom.