Scientific or graphing calculator? What do students need to purchase? As your kids get older, that school supply list may get shorter, however, it's not necessarily less expensive. One item that can cause sticker shock to parents of high and middle school students is an specialized calculator. A majority of schools prefer that students possess their own hand-held scientific calculator. In the top math classes, like AP Calculus , a graphing calculator may be required. But, what's the real difference? A scientific calculator can perform tasks in addition, subtraction division and multiplication. The most common scientific calculators have specific buttons for parentheses trigonometric calculations, exponents inverted numbers and pi among others. A graphing calculator does even more. It'll have a larger screen, allowing you to type in a function, after which you can see a graph for it. The Best Buy's Geek Squad agent Derek Meister says scientific calcula...