Extreme fun in extreme cold

​Guess the temperature

The next time it snows, see if you can guess the temperature by observing the snowfall. If the snowflakes are large and sloppy – like falling popcorn – the temperature is probably near the freezing point of water, 32 degrees. If the snow is like fine sugar, glittering and dry, the temperature is probably much colder. Check an outdoor thermometer to see how well you guessed the temperature.

Experiment with freezing things

On a frigid day when the temperature is near zero (on one side or the other), put a variety of things outside to freeze. What happens when you freeze a raw egg? Try one in the shell, one out. What about freezing a rubber band, a plastic cup filled to the top with water, a wadded-up piece of wet cloth, a wet piece of paper, a banana? Fill several plastic cups partly full, each with a different liquid –   water, milk, coke, vinegar, etc. Is there any difference in the way they freeze? Try adding something to each of several cups of water before freezing them – sugar, salt (at least 1/4 cup), corn starch, honey, lemon juice. Keep experimenting.

Listen ...

As you walk in snow, listen carefully. Do you hear a crunching sound or do you hear a squeak? Snow squeaks under your weight if the temperature is around 14 degrees F or colder. Scientists haven’t yet found an explanation that fully explains why this happens.

Is this a good day for snowballs?

You probably already know that it’s harder to make a good snowball on a very cold day (when there is less moisture in the snow) than on a warmer day. Try making snowballs on different days with different temperatures. Write down your observations. What did you conclude?

Look for ice

Look for ice in icicles, puddles, creeks, or ponds. Look for other frozen water. How do the different forms of ice compare? If you observe a frozen pond, look for animal tracks, especially if the ice is covered with snow. Don't walk on the ice! 

​I'm not sure why this shallow puddle froze with such interesting crystals....