13 year old boy creates nuclear fusion at school!

Well, I think that the kid spent about ten times what was needed.
I saw a design for a Farnsworth Fusor in "MAKE:" Magazine (#36 I think).
Your best Neutron detectors would be a Boron Tube Geiger Counter or Helium 3.
Both Boron and Helium 3 have high affinities for free Neutrons.

worth noting that the farnsworth fusor evolved into a more efficient design called a polywell and it is still a contender for the race to commercial fusion power.

EDIT: I do not think the boy's design is derived from the farnsworth fusor because those involved a largish spherical grid electrode and a lot more plasma glow than what was pictured in the OP's piece.

That's a very crude picture.

You can get fusion the way the picture is done - it's just less efficient than a fusor, which is pretty bad in itself.

If the thing is actually the way the picture is, they're just honking two deuterium beams at each other and trying to get some head-on collisions that overcome the Coulomb barrier. That'll work, but you have worse odds than if you have them happily zipping around trying to get to the center of the fusor's inner ball and missing.

Another way to do this that'll work for demonstrations is to get some lithium deuteride for a target and shoot it with high speed deuterons or tritons. That gives you a lot better odds of getting fusion than head-on collision in two beams, unless you've got really collimated high current beams, which I wouldn't expect a kid to manage.

IIRC, that's the first way fusion was ever proven, too, a deuteride target and some deuterons in a beam.

Fair play to the kid. Beats spending all your spare time on gtav.
It's good to see the support of his teachers too. There's a lesson for other schools in this story.

I wonder which agency/research facility will hire him. Hm...

Dam all i can say is he is the real life Jimmy Neutron.