Using a calculator

Calculators in school

Educators usually avoid using calculators before Algebra I. When calculators are introduced too early they become a crutch preventing students from developing flexibility and skill in basic math facts. Such students often struggle later to develop the symbolic understanding that is essential for higher mathematics because they are quickly lost by the multiple arithmetic calculations embedded with more complex algebra problems. These students may believe they are "bad at math" when they simply never learned the fundamentals. These fundamentals include:

1. Multiplication tables at least through 12 x 12
2. Number base systems and place value
3. Fractions, decimals, and percents
4. The order of operations (PEMDAS or GEMS)
5. The axioms of addition and multiplication (associative, commutative, distributive, identity,  and inverse properties)

On the other hand, calculators are helpful when studying operations that require multiple repetitive calculations, such as exponential functions. Removing the drudgery of a large series of underlying arithmetical operations allows students to focus on higher level concepts. In such cases it is assumed that students have mastered the basic arithmetic concepts.

Choosing a calculator

It's probably best to purchase a calculator that will serve through high school. Depending on your goals, such calculators can be purchased for as little as $5 or for well over $150.  For ecological reasons as well as for simple convenience, a solar powered calculator is a great option. If possible, check with your high school math department in advance before making a purchase.

Given the continuing convergence of digital technologies, it's probably best not to purchase an expensive calculator unless you are sure you'll need it within the next few years.  For example, cell phones are beginning to offer calculator programs that rival high end hand held calculators. This new competition may soon force substantially lower prices for premium calculators.

Types of calculators

Calculators for use in high school and college mathematics come in three major categories.

	Scientific calculators Scientific calculators have the basic functions used for algebra I and trigonometry. They work well for many students and are cheap ($5-$20). The TI-30 series is a typical example. Sharp and Casio make excellent calculators in this category that often provide more features and are less expensive than the TI equivalent. These calculators are ideal for students who do not plan to enroll in college preparatory math.
	Graphing Calculators Graphing calculators allow students to view graphs of equations. Courses such as Trigonometry, Algebra II, and Calculus require the use of graphing functions. Graphing is a powerful teaching tool as the ability to view a visual model of equations can be crucial to understanding. Graphical problem solving methods are also helpful in quickly estimating an answer. Such skills may be critical for standardized tests, such as the SAT and ACT exams where a student has only about a minute to answer each problem. Popular graphing calculators include the Texas Instruments TI-83, TI-84, and TI-89 series. Prices are usually from about $90 to $150. An excellent choice in this category is the TI-83 Plus, which is allowed in ACT and SAT exams, AP classes, and most college math courses. These calculators are ideal for students who plan to enroll in college preparatory math, but do not plan to pursue an advanced scientific or engineering career in college.
	Computer Algebraic Systems (CAS) Computer Algebraic Systems (CAS) calculators provide the ability to graph AND the ability to solve algebraic (and often calculus) equations. These calculators are very powerful – and as such are NOT allowed on the ACT. (CAS calculators are allowed on the SAT.) CAS calculators provide all the tools needed for the most high powered math courses. The TI-89 series is perhaps the most popular of these with prices in the $150+ range. These calculators are ideal for students planning on a college degree in mathematics or engineering.