• HP produces a graphing calculator that can help in math classes.Jupiterimages/BananaStock/Getty Images
  
  Hewlett-Packard, or HP, was established in 1939 by Bill Hewlett and Dave Packard, who were classmates at Stanford University. The company's first product was an electronic instrument for tests performed by sound engineers called an audio oscillator. Over the years, HP has continued to make office and home products, including calculators. The company has various calculators that perform financial, graphing and basic functions.
  
  

HP's QuickCalc Calculator

• The HP QuickCalc Calculator cost $5.99 as of October 2010. It features a magnetic backing for attaching to metal objects and also can be attached to a keychain. The calculator has an eight-character display with a numeric keyboard. It is used to perform basic arithmetic. The calculator measures 4.65 inches by 1.73 inches by 5.9 inches.
  
  

HP's 10s Scientific Calculator

• HP's 10s Scientific Calculator provides more than 240 functions, algebraic data entry and runs using a battery or solar power. The calculator not only performs basic math but also has the ability to calculate conversions, trigonometry and statistics. The unit has a 109-character, two-line display. It measures 5.98 inches by 3.2 inches by 0.51 inches. The calculator cost $9.99 as of November 2010.
  
  

HP's 48gll Graphing Calculator

• The HP 48gll Graphing Calculator cost $109.99 as of November 2010. It offers 2-D and 3-D graphics, stores up to 80.7K user memory and creates applications through programming options. The calculator has the ability to share information with other HP calculators and can transfer materials to a computer via an IrDA port. It also has a 12-character display screen, more than 2,300 built-in functions and an alphanumeric keyboard. The calculator measures 7.2 inches by 3.4 inches by 9 inches.