Calculators that add fractions can be found both in-store and online at retailers such as Walmart, Sears and Office Depot. Prices and availability vary by brand of calculator, store and location.
Walmart and Sears both carry the Educational Insights See'N'Solve Fraction Calculator. The See'N'Solve Fraction Calculator is geared towards children between 8 and 11 years old, and allows children to add, subtract, multiply and divide fractions. The device requires two AA batteries that are sold separately. Office Depot carries the Casio FX-55 Plus Fraction Calculator. The Casio calculator is geared towards students in general and computes fractions and other mathematical functions.