My younger son asked me if I would help him in calculus this semester. A major request but I acceded. Today's "review" involved factoring polynomials and rationalizing numerators and denominators. I now realize this is stuff I haven't done for perhaps 25 years though I have used algebra occasionally at work. Thank goodness for the internet: a quick google came up with several sites and links with math class lecture notes on how to solve these problems. My son might not have the patience to browse this stuff but at least Dad can relearn and teach him without so much fumbling about.