One of the easiest science experiments for your youngest learners (yet older kids are still fascinated by it) is a simple water cycle bag experiment. It is a great way to introduce them to the science of the water cycle. It is a pretty cool fact that water is the only substance that appears naturally in all three states of matter-solid ( ice or snow), liquid (rain, condensation), and a gas (vapor). You can do this experiment with things you have on hand and home and keep on watching the cycle as long as the kids like-we still have one hanging in a window now.
Water Cycle Bag Experiment Supplies
- A quart zip top bag
- Permanent marker.
- Optional- blue food coloring
- To make it a bit more fun and to help children understand the process better the first thing you want to do is draw land/water and a sun on your bag using a permanent marker. Make a clear water line.
- Next, fill the bag with water just to the water line, add blue food coloring if you wish, again this gives the impression of water and helps kids see the process a bit better.
- Seal your bag well and tape off the top.
- Find a sunny window in the house to hang your bag in, be sure it is secure.
You can explain to your children and then let them experience it by watching what happens in the bag and comparing it to watching the real water cycle at work.
When water absorbs and releases energy from heat it changes into the different states of matter. The first thing you will notice in your bag is that after a while in the sun droplets begin to form inside the walls.
How did that happen?
The water is heated by the sun and turns into a gas (evaporation), when it hits the sides of the bag and cools it becomes solid water again( condensation). As the drops grow larger and heavier they begin to fall back down into the bag (rain). Then the cycle begins all over again.
One fact to point out to your children is that the droplets on the side of the bag are clear, not blue. When the water evaporates the blue food coloring is left behind.