Sunday, August 2, 2009

Nine Gaps promotes thinking and learning

The Nine Gaps game has been around for a couple of months now, and has managed to climb up near to the top of the heap in math applications. Indeed, as I browse through the 10 math apps above it, I think it deserves to be on top.

In the game, the player is challenged to position the digits 1 through 9 onto a 3x3 equation grid such that all of the equations formed (horizontal and vertical) are true. Although it has a passing similarity to Sudoku – it is much more worthwhile. The user interface is clean and simple and a pleasure to use. Everything seems to work as it should and players are never distracted by the interface as they work on solving the puzzle.

I like Nine Gaps because it is a creative game that challenges the player to problem solve and think through multiple possible expressions as they search for solutions for each of the 6 equations on the board. It provides simple but very effective feedback in the form of sounds (positive and negative) and color (green means the completed equation is true and red means that the completed equation is false). The goal is to minimize the time taken to complete the game, but because players can’t really achieve a good time by grinding or guessing, they are encouraged to think through their choices systematically and even undo correct equations if further explorations identify a dead end. This type of game – where the players are challenged to examine and evaluate the multiple possible expressions is a great tool for helping students to think logically, refine accuracy and build fluency in basic facts.

The only gripe that I have with Nine Gaps app is that the order of operations convention is not followed. Players are forced to ignore the precedence rules and follow the game rule of calculating from right to left or top to bottom. Although this quirk may not a big problem for adults who have mastered the convention or even perhaps only minimally so for children who have not yet been introduced to it, it may be distracting and unhelpful to students who are just learning to apply such (typically ages 11-12). Perhaps the authors of this program could add a setting whereby parentheses could optionally be included on the game board to support the learning of this important convention.

Nine Gaps has 3 levels of play - the easiest mode gives you a bit of a hint by preloading two of the digits onto the grid in order to provide the player with an obvious next step. At the medium level, a single digit is preloaded into the grid providing the player with two expressions missing only two values reducing the number of combinations that must be tried in order to discover the first workable guess. Finally, the hardest level leaves all 9 positions unfilled – giving the player no explicit hints.

As a math teacher educator, I see Nine Gaps as something much better than a flashcard program for learning basic facts. It is a great tool to offer to teachers and parents seeking to help children to improve their accuracy and fluency with basic facts while simultaneously promoting the development of problem solving and reasoning skills. I’m impressed with Nine Gaps and I intend to keep it on my Touch for a while.


Karen Jacobs said...

Love the game and at 72 I can use the exercise ;) Can you suggest any similar games for regular computer use? The g-kids could use the exercise as well as school nears.

Tim Pelton said...

Yes, I see the potential for these types of apps supporting parents and grandparents - both in renewing their math mastery and in some cases developing it for the first time.

There aren't many apps that I would endorse yet. Too many of them are simply challenging people to remember facts without giving any substantial encouragement toward building a conceptual understanding or problem solving.

See my next entry for a list of apps I like right now...

Tim Pelton said...

Sorry, I missed your mention of a regular computer. I haven't been focussing on computer apps right now and only have a couple of suggestions for applications that support creative explorations:

Scratch - a neat introduction to computer programming found at

Comic life: a great tool to support kids as they represent and communicate their understandings. Find it at

LEGO Mindstorms NXT - robotics to support hands-on learning - check out FIRST LEGO League too.

Still, I think that these new devices (touch/iphone) have a great potential to take learning applications to places where kids have a few moments and are willing to work with their parents or grandparents - anytime-anyplace learning.

Karen Jacobs said...

Thanks... the g-kids love my iPhone apps and will probably have their own someday. Math has always been my weak link, but I love puzzles so Nine Gaps works! I'll check out your suggestions...

Unknown said...

Hey!! Have played this on a friend's iPhone... Any chance at all of porting it to the Droid??? Would be a mega-seller!!!

Steve in Texas