Scientific Calculator
Casio fx-300MS Scientific Calculator
"Casio Plus scientific calculator offers 229 in-built functions such as fraction/decimal conversions, trigonometry, fractions, regression analysis and more. Scientific calculator includes slide-on hard case and 2-line display for easy reading."
For more information: http://support.casio.com/storage/en/manual/pdf/EN/004/fx-82SX_220PLUS_etc_EN.pdf
Price: $8 per quarter