Students should be experimenters. Performing experiments is central in mathematical
research,but experimenting is all too rare in mathematics classrooms.
Simple ideas like recording results,keeping all but one variable fixed,trying very
small or very large numbers,and varying parameters in regular ways are missing
from the backgrounds of many high school students. When faced with a mathematical
problem,a student should immediately start playing with it,using strategies
that have proved successful in the past. Students should also be used to performing
thought experiments,so that,without writing anything down,they can give
evidence for their answers to questions like,“What kind of number do you get if
you square an odd number?’
Students should also develop a healthy skepticism for experimental results. Results
from empirical research can often suggest conjectures,and occasionally they
can point to theoretical justifications. But mathematics is more than data-driven
discovery,and students need to realize the limitations of the experimental method.