What the Snowshoe Hare Teaches Us About Integrated Science Units

“Wait, if the snow keeps melting earlier, and hares are still turning white too soon, doesn’t that mean the wrong camouflage is making them easier to catch? So wouldn’t that eventually change the genes of hares long-term?” a curious seventh-grade life science student questioned. Another followed up, “What’s a gene?”

It was a classic teaching moment for me, equal parts magic and mess. On one side, they were making connections between ecology, genetics, and evolution. On the other side, my curriculum was designed to teach in units on ecology before we got to genetics and evolution. But honestly? This classic teaching moment changed the way I taught. The real question they were asking wasn’t just about genetics or ecology. They were really wondering: “Why aren’t we learning science in the way it actually works—interconnected?”

In our natural world, organisms, energy, genes, and evolution are all tangled together; in school, we often chop up many subjects like science into neat little boxes: cells unit, photosynthesis unit, ecology unit, genetic units, and finally an evolution unit. Nature doesn’t work in units, so why do we teach it that way?

To answer this question, I began redesigning the life science curriculum into interconnected units anchored in real-world phenomena. Each unit now unfolds like a story line—starting with a compelling question and weaving together life science standards and topics like ecology, genetics, and evolution. Rather than isolating content, the stories now build systems thinking where one scientific idea connects naturally into the next, helping students see the patterns and relationships that make up our natural world.

If It’s Disconnected, It Doesn’t Stick

Dr. Anita Archer says, “How well you teach equals how well they learn.” Before, students spent four to 10 weeks on each isolated unit, often having reteaching within the unit where necessary. If I teach science as disconnected units, I’m showing students that those concepts aren’t related, even when they clearly are. I needed to cut the fluff and focus on what mattered most: sensemaking, systems thinking, and applying scientific skills like modeling, analyzing data, and reasoning in more meaningful ways.

My students connected predators to gene flow and selective pressures before we’d cracked open those units. They didn’t see separate chapters: Instead they saw a system. As a teacher who wants to inspire future generations of scientists and researchers, that’s the exact mindset I needed to build.

Integrated science curricula or story lines, especially those rooted in real-world phenomena and data, have been shown to improve student understanding and retention. When a student sees how climate change can affect camouflage, which influences predator-prey dynamics, which connects to selective pressure on genetic traits… they’re not just memorizing facts, they’re building a mental model of how life actually works. Now, reteaching doesn’t just happen within the unit, but as we cycle back to standards, we can reteach and build on those concepts more efficiently. The connections help students retain and apply knowledge more readily, and we even have more time for extension activities for students already proficient.

How to Start Redesigning

Start with a phenomenon. Something puzzling or fascinating, concepts you love, or something that is just plain cool. Ask yourself: What’s going on here? What standards or core science ideas help explain this?

Then start backward designing. What do you want students to understand, to be able to explain, and what skills will they master by the end? What connections do you want them to make across systems—ecological, physical, and biological?

From here, you can design lessons that build, not just follow a sequence. Instead of a flat list of objectives, think of your unit as a story, one that invites students to keep asking why and what if? I like to think in terms of questions that evolve across the unit.

As I designed each unit, I mapped out the NGSS standards in a way that made sense conceptually, connecting the performance expectations across life science domains like ecosystems, heredity, and evolution, or another unit connecting ecosystems, structure and function, and evolution. This allowed each phenomenon to serve as a hub for multiple standards and domains rather than a single topic.

A Real Example: Snowshoe Hare Phenomenon

I designed a unit around two compelling images: two different snowshoe hares, one brown and one white, sitting on brown, snowless ground. I asked my students to come up with wonderings, and the chatter began: “Why would they be two different colors? Maybe they are different species because one is camouflaged and the other isn’t? No, I think the snow melted and one hare changed, but can it change fur color?” And just like that, we were off!

The story starts with students investigating predator-prey dynamics, molting patterns, and climate change. From there, we zoom into the molecular level—gene expression, proteins, and the pigment that causes hares’ seasonal fur color.

Students explore why not all hares change at the same time and how that genetic variation creates different survival outcomes depending on the conditions. We simulate survival scenarios, examine trait frequency data, and study how pressures like snow cover, or lack of snow, can shift gene pools over time.

By the end, students can explain how climate change affects camouflage, which alters predator-prey relationships, which connects to new selective pressures, ultimately shaping the genes passed to future generations. They make meaningful connections between ecology, genes, and evolution in a way that feels like science, not just school.

Their final task? Build a scientific argument, supported by data and models, to answer the story’s driving question: How is climate change affecting snowshoe hares, and how could that lead to long-term changes in their genes?” The skills they gain and the depth of their thinking is inspiring.

The rest of the year follows a model similar to this unit, with students investigating antibiotic resistance to understand natural selection and genetic mutations; in another unit they explore ecosystems and heredity in Yellowstone; and in another unit they investigate ecosystems and natural selection in the Galapagos Islands. Each unit tells a different scientific story, but they all build toward the same bigger picture, connecting concepts to investigate real-world phenomena.

Helping Students See the Bigger Picture

That single student question, “Wouldn’t that eventually change their genes?” wasn’t just a spark, it was a call to action—a reminder that our students are capable of deeper thinking when we give them the space to connect ideas across units. This kind of teaching helps students understand the world—not as a list of science terms and multiple choice tests, but as a network of relationships. When we teach science the way it works, in context, in connection, students don’t just learn more, they remember it, apply it, and start asking better questions that lead to even more connections. And sometimes… those questions just might change us, too.