Teachable Moment: I'm not sure what I like more about this idea: the practical nature of it or the fact that the correlation between temperature and cricket chirp rate was documented by one of the inventors of the radio telephone.
From Farmer's Almanac:
Did you know that you can tell the temperature by counting the chirps of a cricket? It's true! Here's the formula:
To convert cricket chirps to degrees Fahrenheit, count number of chirps in 14 seconds then add 40 to get temperature.
Example: 30 chirps + 40 = 70° F
To convert cricket chirps to degrees Celsius, count number of chirps in 25 seconds, divide by 3, then add 4 to get temperature.
Example: 48 chirps /(divided by) 3 + 4 = 20° C