And then it hit me. It's the feedback!
The feedback that players get in Bounty Hunter is very personal. An answer is not right or wrong, it either fits with their plan or it doesn't.
Let's think about a typical review game that we might play in our classrooms. I play review games where I will give the students a question and they have to answer it correctly. If they do, their team gets points, or gets to move their pawn, or something. For example, here is a question I would give:
Determine the slope of this line:
If the student gives me a correct answer of -3/2, I'll give their team 10 points. But what about the feedback for an incorrect answer? I know that some students will listen to my explanation, but others will tune me out. They may not even know that I'm talking, they are getting ready for the next question. In this case, the feedback that is given may or may not reach the student.
I'd like to show you a move in Bounty Hunter:
For this game, let's suppose we are the yellow jewel thief. We want to land on the pink gem and we want to avoid the red bounty hunter. If we create a slope of -2/1 our jewel thief will land on the pink gem (yay!). However, if we accidentally create a slope of 2/1 we would land on the bounty hunter and be captured (no!). You can imagine that a player's reaction might be more intense in this game compared to the other review games I play in my class.
The Quality and Importance of the Feedback Matters.
In Bounty Hunter, there is no right or wrong slope. But the move you make may not be what you wanted it to be. That is an important difference from my typical review game where there is only one correct answer.
Once game play starts, the players start to develop a plan. It's personal, and they created it. If they do something mathematically that doesn't fit with their plan, they're going to want to know why. This makes the feedback important to the player. In the example above, if we create that accidental slope of 2/1 and expect our jewel thief to move down and right, but see him move down and left, then we are going to want answers. We might even yell out.
On the other hand, it's very satisfying to see your character move as you expected. There is more than one reward to creating the slope you expected: The player will see what they anticipated (reward) and the player lands on the pink gem (reward).
So, What Makes Bounty Hunter So Special? The feedback that the students receive from the game is personal, important, and nonjudgmental.