The boy's face is nicely lit by the nintendo screen - and the black and white conversion does a good job of covering any potential colour cast. I like the composition, the eye is naturally drawn from the boy's eye to the nintendo, and there is nothing distracting in the background. For the purpose of challenge entries I would suggest investing in some noise reduction software (neat image or noise ninja) - although it doesn't bother me and I think it adds to the shot in this case, you will be marked down for noisy images.
Truly good conversions to black and white are difficult and this is a good example of the zone system and how it impacts an image. In this instance a technical success isn't quite the artistic success it should be. While a good candid look at an introspective moment, the subject is short of having some sort of pop or wow factor that provides the image with some impact - it's just a candid moment. While photographers can't always be in the right place at the right time with the right camera and the right lens, this might have been improved by taking a longer look and include some more detail of the background and providing context of the subject playing the game. A good solid entry into the challenge.