Using Science Simulations and Models
When teaching kids the water cycle, how do we make the invisible visible? When scientists ask this question, they often answer by building a model or simulation, which is what we’ll do here. Kids find this water cycle activity to be super engaging—they’ll keep going through the cycle until I make them stop. Plus, it provides excellent fodder for discussion. Let’s dig in!
We set up 10 stations, each is a different locale where water collects. Each station has a sign identifying it, a bowl of beads, and a stack of cards with instructions. Kids get a pipe cleaner to start and may begin at any station. At each station, they add a bead to their pipe cleaner, read a card to find out what happens to them and where to go next, and then return the card to the bottom of the stack before heading to their next locale. For instance, if they’re at the Dew station, their card might say, "You evaporate and turn into a gas. You are now humidity". So, they head to the humidity station, add a bead to their pipe cleaner, read the next card from the stack, head to the next station, and so on.
This will go on indefinitely until you interrupt! I like to stop them midway and ask them to pay attention to the elaborate paths they’re taking and how their path differs from everyone else’s. Is this modeling what’s happening in real life? Can we learn multiple things from a model? Yessiree!
Scientific Models Are Accurate
The path that kids trace through the water cycle is complicated but not random. You can’t simply roll a pair of dice or spin a spinner to tell you where to go next. Why? Because not every location on the water cycle connects directly to every other location. We show this by using cards that tell kids where they are and where to go next. There’s a randomizing which card they choose, however the cards limit their options to the obvious next locations.
Scientific models have layers and depth
Does water trace a pattern through its cycle? Yes, and no. There’s a complexity of motion clear in this model, which mirrors the complexity of motion clear in the water cycle. If you watch the class moving around, this is fun to watch the intricacy of motion as the kids move from station to station. Often they are so focused on getting their next bead, they lose sight of this and it needs to be brought to their attention.
Water can move from one locale to the next and back again. Notice that some colors of beads can only show next to other colors because of the way water does and doesn’t move through the cycle. But overall, there’s no discernible pattern and each stack of beads will be unique as long as the simulation goes on long enough.
Scientific Models Teach Multiple Concepts
Here are a few things we discuss during this lab. 1) The water cycle is not a circle. Kids can develop this false idea if their only exposure is making and studying water cycle diagrams. The kinesthetic nature of this activity dispels that without having to teach it explicitly. 2) Water is in constant motion. A water molecule may remain in a location for thousands of years or a single moment. Water is moving to different locations all the time. 3) The concept of states of matter is embedded in this activity and there are plenty of places to discuss it. 4) If you also teach about the types of bodies of water, you could discuss the ones mentioned in this activity.
Some Scientific Models Are Better Than Others
I prefer this model to those that use dice or spinners. While there is a randomness to how water moves through its cycle, there are paths it travels and paths it doesn’t. For instance, groundwater doesn’t turn into a cloud without a few intermediate steps. These are baked into our model since the cards direct kids from one location to the next. So from the ocean you might go to ice or humidity, but you wouldn’t go to a lake or river.
Scientific Models Produce Challenges
Some kids may become frustrated by being stuck in a loop. This is true for water molecules too (though I’m not sure they get frustrated!) Water can endlessly evaporate —> condense —> rain —> evaporate. The longer that students continue the simulation, the more likely they will visit more locations. Is this guaranteed? Nope!!
Scientific Models Have Limits
Most water moves through plants as shown in the model here, but a small fraction splits into its elements (oxygen and hydrogen) during photosynthesis. There are always more layers of complexity. Will you have this discussion with fourth and fifth graders? Probably not! But it’s helpful to know that this is only part of the story of water.
Scientific Models Connect to Other Scientific Concepts
An obvious conceptual connection to the water cycle is change of state. Whether you’ve taught this in the past or plan to do so in the future, consider commenting on the various states of matter and phase changes they’re seeing on their journey through the water cycle.
Have you done a water cycle activity like this? How did it go? You can certainly make your own, but if you want one that’s done for you, check it out on the website here. Or if you prefer, you can find it at my Teachers Pay Teachers store, here.
