My 8yo twins received this for review and were actually excited to practice math with it during their summer vacation!  It requires 2 AA batteries in a rear compartment that can be unscrewed with a coin.  As stated in other reviews, the battery door bulges with the batteries inside although it does not affect the function. The screen is a very basic design typical of a calculator but with functions that allow testing in addition, subtraction, multiplication, division, decimals, fractions and percentiles.  There are 9 levels for each function and a help button to provide clues.  It's simple enough that my 6yo was able to figure it out and the green and red light next to the screen lets the player know if they have the correct answer.  It's great for building math skills and since my kids are happy to play with it as an electronic toy I'm very happy