One of my philosophies of outdoor teaching -- any teaching for that matter -- is to follow the students’ interests: take something they want to do anyway, and figure out a way to make it a lesson, or at least tie it in. If you are lucky enough to teach where there is snow, this is easy to do. What do kids want to do with the snow?
THROW IT! I figured out a way to incorporate this into a snow science lesson. For the introduction, I had a student make a really good snowball, then we used that snowball as a “talking object” to toss around the circle and have each student share what they knew about snow. By the end of the sharing session, the snowball was changing -- and that led into a discussion of what snow is made of and how it changes after falling onto the ground. Then, all the students make hard-packed snow-balls and we made hypotheses about what would happen to them after we threw them in the creek. We held a “snowball race” and students learned that snow has a lot of air in it, because their snowballs floated instead of sinking or melting right away. (This can lead to some great water cycle stories, as students try to follow their snowball’s journey as it goes downstream and melts -- good introduction for watershed lessons, too. Most of the students live “downstream,” so they could figure out how their snowball eventually will make it to their house!)
SCULPT IT! The presence of so much air in the snow led to discussion of snow as a shelter for wildlife (the trapped air insulates). Building snow shelters, even if squirrel-sized, is something that can help students understand the sub-nivean habitat. This leads to a lesson on winter adaptations where students work in teams to create snow creatures complete with adaptations for surviving in this habitat. We have a gallery showing afterwards, with each group sharing about their creature’s adaptations, ecological niche, etc. After the show, they have a choice to leave their creature, or I sometimes set up a snowball “shooting gallery,” and let them get the snow throwing out of their system on their creatures. (HA - it’s never out of their system! But if I can use that as a reward for good behavior (i.e., not throwing snow all day), at least it is in a very controlled and safe setting.)
EAT IT! The fact that students want to eat snow can pique their interest in finding out what’s IN snow. Bring some samples from different layers of the snow inside where you can melt it on a burner, then pour the melted snow through a coffee filter (basket type, not cone). Students are always amazed at how much dirt there is in even the whitest snow. This helps quite a bit in deterring them from eating it! (We don’t usually let students eat snow because they will pick up snow from anywhere and eat it, and there are some diarrhea-causing organisms that can live in snow, such as the “watermelon snow” bacteria.) On the other hand, when it's at its freshest and untouched, sometimes bringing along sugar-sweetened Kool-Aid and making sno-cones can be a great treat!
CATCH IT! One way I do let students eat snow is by catching the falling snowflakes on their tongues. If you have some dark-colored boards which have been kept cold, you can catch snowflakes for observation with a hand lens. You can even make up snowflake ID charts to have students figure out what kind of snow is falling, then learn what kind of atmospheric conditions create the different types of snow. Most of the snow we get in southern California is graupel (a “real” snowflake buried somewhere inside a miniature snowball of frost) or wet snow that melts as soon as it hits the ground. Conditions are always changing, however, and if you check often , you can get some beautiful “classic” snowflakes. You can do statistics on the snowflakes, figure out what percentage are stellar crystals, what are spatial dendrites, what are graupel, then think about how the different types of snow might affect the plants and animals - the spatial dendrites stick together on branches and can cause them to break, the needle crystals slide past each other more easily and can lead to avalanche danger, for example.
DIG IT! Making a snow pit can be very interesting - you can see and measure different layers of snow, estimate how many storms that represents, look at the metamorphosis of snow in the different layers, estimate water content, etc. To estimate water content of the snow, take a graduated cylinder (or just a jar or cup, for that matter) and fill it with snow from a particular layer - trying not to pack it more than it already is, and have students estimate (guess) how much water there will be in the cylinder after the snow melts. Students are always amazed at how little water there is in snow! But then again, that's why those snowballs floated, isn't it? Once you've dug your snow pit and taken measurements, you could use the pit as the start to a Quinzhee or Igloo or other type of snow shelter if you have time for that - just be careful about making ventilation holes.
So, don’t come in from the cold! Get out there and channel your students’ energies and enthusiasm into some hands-on lessons about winter ecology and the physics of snow. It’s amazing how quickly they will forget their cold toes as long as they are having fun.