When Stillwater Area High School junior Peter Jansen walks out of sight, his latest Advanced Placement Biology experiment starts "cheeping like crazy."

That's because Perry, a three-week-old white-crested duck, imprinted on Jansen shortly after hatching. Now Perry follows Jansen around as much as he's allowed to — and has already been kicked out of math class because he couldn't keep quiet.

"I've learned how hard it is to be a father," Jansen said with a laugh.

Perry is one of three ducklings helping teach Andy Weaver's AP Biology and AP Environmental Science students about imprinting — when a young animal fixes its attention and trust on something or someone it sees as a caregiver — plus some bonus lessons about the responsibilities of parenthood. The students completed their Advanced Placement test at the beginning of the month, so they're working on hands-on projects for the remainder of the year.

It's a longstanding tradition at Stillwater High for waddling waterfowl to be one of those projects. Years ago, Weaver had up to 30 ducklings imprinting on students. But that proved a bit of a distraction in the school.

"It may look overwhelming in here now, but there used to be a lot more chaos," Weaver said about his classroom, where nearly every inch of counter space is covered with some iteration of an end-of-the-year student project involving plants or animals, both dead and alive.

Weaver has already started packing up some parts of his classroom and his many collections of furs, skins and taxidermied critters. And he recently rehomed the classroom pets — Julius Squeezer, a ball python, and Fuego, a bearded dragon.

After 33 years at Stillwater High, Mr. Weaver is retiring.

"Andy is the teacher that students want to have and that parents want their kids to have," Principal Robert Bach said. "Kids learn by doing in his class."

Outdoors as learning playground

Weaver has made sure there's a lot to do. Students helped with fish hatching, maple syrup tapping, deer tracking, migratory bird banding and raptor propagation. (Because Weaver is a falconer, the high school is home to captive peregrine falcons as part of a breeding program.)

Much of that is possible because of grants Weaver has secured and licenses he holds, as well as the convenient nature access provided by a 55-acre parcel called the Environmental Learning Center located just behind the high school.

"It's like our playground," Weaver said. "For these 'get your hands dirty' kind of kids, those opportunities are a big deal. And they make a long-lasting impression."

Senior Katelyn Stack said Weaver is her favorite teacher because his passion for the outdoors is contagious.

"He also really cares about his students, and his classes are more fun and interactive than any others — and this is a good example of that," she said while holding Woodstock, the duck who imprinted on her a few weeks ago.

Woodstock has gotten increasingly speedy at the wooden maze in the classroom that tests his memory and intelligence. Stack will write her final paper on the duck's ability to learn.

Stack and Jansen said it's not just the ducklings who feel a sense of attachment. The students — and their families — have taken to the birds as well. Students take the ducks home in small pet carriers.

Stack's dad, who was initially against having Woodstock in the house, now lets the bird sit with him on the couch. And Jansen's dad hangs out with Perry in the garage.

Woodstock, Perry and Killer (the class duck — imprinted on Weaver) will be rehomed to local farms. The ducks will adjust without their teenage "parents," though they'll likely spend their lives seeking human attention, Weaver said.

Jansen said he'll miss his fluffy school project, but he'll be able to visit.

"Once you get to know him, you find out Perry is really friendly and loving," Jansen said. "I'm definitely a proud duck dad."