comparisons with national Averages. Choose several variables that are relatively easy to measure in a class or sample of students. The variables should involve a quantity that can be averaged (for example, height, weight, family size, blood pressure, heart rate, reaction time). Use the Internet or other references to determine national averages

(means) for these variables (by age categories, if appropriate). Collect data on the variables, using a random sample of at least 50 individuals. Carry out the relevant hypothesis test to determine whether the sample mean differs significantly from the population mean.