MathShark is a skill building calculator that sharpens mental math skills from basic math facts to pre-algebra practice. MathShark is great for individual, self-directed time testing of addition, subtraction, multiplication, division, fractions, decimals, and percents with 8 levels of difficulty for each basic operation. Math problems are displayed on the LCD both horizontally and vertically. Lights and tones are displayed to make the students’ learning experience fun and exciting. Sound can be turned off for silent classroom requirements. For grades 1 and up.