Five Kakooma iPhone/iPad apps are available on the App Store:

  1. Kakooma Addition (sums to 25)

  2. Kakooma Addition Pro (sums to 99)
  3. Kakooma Negatives (sums from -15 to 15)
  4. Kakooma Times (multiplication tables up to 9)
  5. Kakooma Times Pro (multiplication tables up to 20)

The more challenging Pro editions offer a higher degree of difficulty than the basic apps. We hope to have Android and Kindle versions soon.

To purchase an app, click the image below:

You can play Kakooma online and download print versions for free. To try Kakooma fractions, click the icon below.

History. Greg Tang invented the math puzzle Kakooma in a coffee shop in Arlington, Massachusetts. The name comes from the Spanish word cacumen – which means keen insight or mental sharpness. Kakooma won't make you fluent in Spanish, but it will sharpen your mind and make you better in math.

Kakooma is a puzzle based on a deceptively simple idea: in a group of numbers, find the one number that is the sum of two others. Sounds easy, right? Sometimes it is, but other times the answer is right in front of you and you just can’t see it.

Fact Fluency. To solve a single Kakooma puzzle, players end up doing lots and lots of calculations in their head. All this mental math sharpens their mind, improves their number sense, and helps them master their math facts. And kids think they're just having fun!

In April 2011, at a Title I school in Baltimore, two 5th grade classes participated in an iPad project in which the students played math apps for 15 minutes a day. After just one month, 3 students had solved a 9-number Kakooma puzzle in less than 20 seconds (the average time for adults is nearly 3 minutes). James, the fastest student, was videotaped by his principal solving a puzzle in 11 seconds. One week later he lowered his time to an amazing 8 seconds – a new world record!