1. First, you will need a plastic bottle. (A 20 ounce plastic soda bottle will do the trick. Just make sure it is clean and dry before the activity!) Place some ice shavings in your bottle. In your journal, be sure that you record the amount of ice shavings (or snow) you place into your bottle. You may want to record the level on your bottle with the date.

2. Freeze the bottle overnight. Allow your bottle to thaw just a few minutes and record the height of the ice/snow. Also, record any observations you make about the contents of your bottle (your sample). You may want to draw a picture of your "ice core," illustrating the observations you have made and labeling important features. Add more snow to your bottle and refreeze overnight.