There are two main ways of measuring temperature. One is called Fahrenheit (after the man who invented it) and the other is called Centigrade (meaning 100 degrees). They measure the same thing, only they start counting at different temperatures and the size of the degrees is different (Centigrade degrees are bigger than Fahrenheit degrees).
Fahrenheit is used only in the United States. In Fahrenheit, the temperature where water freezes into ice is called 32 degrees, and the temperature where water boils is called 212 degrees. Normal human body temperature is 98.6 degrees.
Centigrade (which is also called Celsius after the man who invented it) is used everywhere else in the world. In Centigrade, the temperature where water freezes into ice is called 0 (zero) degrees, and the temperature where water boils is called 100 degrees. Normal human body temperature is 37 degrees.
To find out more about temperature, check out these books from Amazon.com or your library:
The Celsius Thermometer (An Early Metric Book), by William J. Shimek, George Overlie (1975).
Temperature (Measuring the Weather), by Alan Rodgers, Angella Streluk (2002).
Science Projects About Temperature and Heat, by Robert Gardner, Eric Kemer (1994)