
MATERIALS
 mathematical worksheet (optional)
 examples of use of the Celsius scale
 student journals



PROCEDURE




Activity
 Display the following conversion formulas for student reference:

TEMPERATURE CONVERSION 
CELSIUS 
°C (9/5 °C)+ 32 = °F 
FAHRENHEIT 
°F 5/9 (°F  32) = °C 
 Identify the freezing points and boiling points for both the
Celsius and Fahrenheit scales.
 As a group, use the conversion formula to find the Fahrenheit
equivalent of 21°C.
 Enter the conversion formula in the student journals and challenge
students to calculate the Celsius equivalents of several Fahrenheit
temperatures and Fahrenheit equivalents of several Celsius temperatures.
 Discuss the advantages and disadvantages of both systems.
 This "standard" formula is based on converting at the freezing
point of water. This requires the addition (sometimes) and the
subtraction (sometimes) of "32"  and this can be somewhat confusing.
On the other hand, if the coversion is done at the temperature
that is the same on both scales  which is "40" degrees
 there is little room for confusion. Think of it this way:
 9/5 is greater than one, and will increase a value. The
Fahrenheit scale ALWAYS has a larger value than the corresponding
Celsius temperature.
 5/9 is less than one, and will decrease a value. The Celsius
scale ALWAYS has a smaller value than the corresponding Fahrenheit
temperature.
 When given a temperature in either Fahrenheit or Celsius,
add 40 to it.
 Then multiply by the appropriate factor:
 by 9/5 if your original temperature is given in
degreesC
 by 5/9 if your original temperature is given in
degreesF
 Then subtract 40.
 Try it! (Is this easier to remember then the conversion
given in the table above?)



Assessment Ideas
 Quickness and accuracy of student conversions using the "standard"
method and the method described in Step 6.





CROSSCURRICULAR IDEAS
 History (research topics): Who were Fahrenheit and Celsius?
Look how these scientist developed these methods for measuring temperature.



VOCABULARY
 temperature: the degree of heat or cold, as measured on a scale.



SOURCE
 Adapted from "Winds of Change" educational CDROM, Copyright
Caltech and NASA/Jet Propulsion Laboratory
 Step 6 conversion approach suggested by Tom Ford, The Science Source

