I have noticed that a number of students seem to be making the same errors on the body mass index program and the temperature conversion program. In order to make a calculation using a user's input, you must first obtain the input. The sequence of your code statement matters.
Suppose you have a program that is supposed to add two numbers. You have to get your values from the user before trying to add the variables together.
INPUT "What is the first number? ", a
INPUT "What is the second number? ", b
LET c = a + b
PRINT a; " + "; b; " = "; c
We'll take another look at the material during tomorrow's class.