By James Floyd Kelly
The number of apps related to teaching various mathematics topics seems to be growing daily, and it can be a difficult to find that needle in a haystack. Here, we found five of those needles, already tested and approved. (These apps are all iOS apps, but a few of them are also available for other operating systems.)
For many more ideas for educational apps of all kinds, look here.
1. Numbers League (iPad)

For young kids, the superhero-versus-supervillain aspect of this game is the big draw. Numbers League's primary gameplay involves adding numbers: A villain is presented with a value (between 3 and 20+) and can only be defeated by combining various superheroes and their respective numbers. Kids can play solo or against other players, and with each turn you roll up a new superhero who has a head, torso, and leg/feet value. Add up the three values, 1/2/4 for example, and you've got a superhero with a total value of 7. A villain with a value of 14 might could be defeated using three heroes with values of 7, 5, and 2, for example. Additional features include special gizmos that can add or subtract numbers (+5, -10, etc.) and these can help combat those high and low valued supervillains.
2. Bugsy's Math Quest (iPad)

Bugsy's Math Quest is all about reinforcing the basic 12 x 12 multiplication table everyone has to learn. Each level has the hero, Bugsy, being confronted by a Boss monster that throws up multiplication problems. The player must quickly type in the answer before Bugsy bumps into the monster. After enough questions, Bugsy takes on the Boss directly to finish out a level. Badges are given out (bronze, silver, gold) based on the player's skill. Parents can access the settings and view a visual graph of which questions were missed and which were answered correctly. As the game progresses, additional levels have the player fill in the blank ("2 x ___ = 8") so the game has plenty to keep a child busy. For kids ready for division, a simple tap on the Multiplication icon in the upper-left corner of the screen turns the game into a Division-based contest. The Math Guide for the app can also be accessed inside the Settings.
3. Bedtime Math (iPhone)

Bedtime Math presents a single screen of text, usually containing a bit of history or other interesting bit of news for youngsters. After reading the single page of text, parents click on three different levels of math problem -- Wee Ones, Little Kids, and Big Kids. One example of a Little Kids question: "If the pool is about 2000 feet long and the Washington Memorial is about 500 feet tall, about how many of those tall Monuments could you lay end to end in the pool?" Because each question doesn't take long to read and work through, parents may find themselves doing three or four questions each night, answering previous topics and questions they've missed. (The questions go back to February 27, 2012, so you've got well over a year's worth of nightly math questions.)