The short answer: it is motivating, individualized, flexible, positive, and it is working.
But with me, there is always a long answer, too:
I attended a technology conference and the key note was Marc Prensky. He was talking about what it is about games that makes kids like them. He said kids like that there are levels to go through, and that there is a goal that you are trying to attain. It immediately clicked in my mind that I could structure my curriculum like that: with levels and an end in sight.
Then I wanted to know more about video games. So I bought James Gee's What Video Games Have to Teach Us About Literacy and Learning. He talked about customizing avatars, gaining status, and having an identity in the game (or in this case, the MathLand context and our classroom). So, I came up with the idea that kids could design an avatar and gain dots when they did something well in MathLand.
And that's pretty much it. From those two main ideas came something that is flexibile, individual, attainable, immediate, collaborative. I aligned the levels to the state curriculum and tried to come up with a variety of ways to present the materials. Group instruction hadn't been working for a long time because it was hard for my students to concentrate and engage when I was talking at the front of the room.
Now, they work on assignments at their own pace. They help each other. And when they need more help than that, they refer to old assignments, textbooks, the computer, or classroom staff. When classroom staff help them, it is individual and personal attention.
Students no longer "fall behind" because they pick up where they left off. Students no longer "skip steps" in the cumulative math curriculum because they can't go much farther ahead without completing the previous level.
The system was naturally reinforcing because they get rewarded regularly for doing well. Every time they accumulate five full days in class (no bathrooms, special activities, etc.) they are rewarded. Every time they finish an assignment, they are rewarded. And so on. And if they finish the levels before the deadline, they get to do bonus opportunities. The bonus opportunities are still academically based, but because they are "bonus" they are rewarding and more palatable.
They also can't do subpar work. Every time they think they are finished with a level they are evaluated by the classroom staff. No putting it in the basket poorly done and not finding out until I have had a chance to go through the basket. Nope. I check it immediately, reteach the parts that they got wrong, and send them back for corrections. Or I pass them on to the next level.
It is a positive system. It is easily adaptable to subject areas and different types of activities. It is aligned to state standards. And it is individually based. From those two ideas came a system that really works with the students and covers the material.
Since beginning MathLand during the second semester of the 2006-2007 school year, I have done a lot more reading. I've read books, reports, and blogs. I've watched videos and slideshows. I've really been adding to my perspectives on technology, game theory, and mathematics. As I evolve, MathLand evolves. It's a fun process for me, too.