I'm sure lots will disagree with me, but I say Javascript.
They already have everything they need on their computer now, and can start right away at JSFiddle and with various online tutorials that run the code on their own machines.
They can do useful stuff right away and share it with people immediately. (for instance, make a little game or graphic gizmo and put it on a web site)
It not only runs on the browser, but runs on the server (node), and in various other environments (MongoDB, Windows 8, etc). So again, their skills can be put to use quickly, and will be useful going forward in the maximum number of places.
There are immense numbers of people out there using it, writing about it, offering help on sites like stackoverflow, and so on.
For kids with short attention spans, the simplicity of javascript is a big plus. Being able to create objects on the fly easily, and not really worry about types and object orientation and all that makes it a lot easier to get up to speed quickly. (yes, there is potential for them to learn bad habits, but I think a far bigger risk is that they get bored and give up)
They already have everything they need on their computer now, and can start right away at JSFiddle and with various online tutorials that run the code on their own machines.
They can do useful stuff right away and share it with people immediately. (for instance, make a little game or graphic gizmo and put it on a web site)
It not only runs on the browser, but runs on the server (node), and in various other environments (MongoDB, Windows 8, etc). So again, their skills can be put to use quickly, and will be useful going forward in the maximum number of places.
There are immense numbers of people out there using it, writing about it, offering help on sites like stackoverflow, and so on.
For kids with short attention spans, the simplicity of javascript is a big plus. Being able to create objects on the fly easily, and not really worry about types and object orientation and all that makes it a lot easier to get up to speed quickly. (yes, there is potential for them to learn bad habits, but I think a far bigger risk is that they get bored and give up)