14 year olds can definitely grasp programming concepts, it's just if they're intersted in it. Maybe an idea would be to show him a free engine to see if he likes the idea of programming, I have a good recommendation;
I started programming at 10 years old with BYOND (Build Your Own Net Dream). it's free, easy to use, excellent forum support, a chat channel for further help, and pleanty of tutorials, snippets and hints for newcommers.
Not only that, but the BYOND engine comes with a free icon editor/creator/animator, a file browser for easy file access, ability for literally hundreds of source files and .dll's, an easy to learn command set, and possibly the best feature of all; a ginormous free server allowing you to make your games go online and have other players join into the game at the click of a button, furthermore you can have multiple games, and everytime you host your game it's posted on BYOND's site as Live allowing other players to connect to the game.
Even more so, BYOND allows you to publish your game when you're done with it and submit it to byond.com, if it passes the very minimal tests it gets posted on their site for other people to host.
Other features include the option of subscription purposes using PayPal, allowing people to send money for upgrades in the game or other add-ons of your choice, and an amazing free Map Editor that shows all of your current icons to the left and allows you to basically drag-and drop them wherever you want, aswell as set their properties afterwards.
As you may have guessed BYOND is only 2D unless you're a masterof trig and can create some basic 3d games as some have done, but the command set is very simple, for example collision in Dark Basic (stopping two images from hitting eachpther like a player and a wall) can sometimes take up to 5 or more lines, in BYOND it's one little phrase:
density = 1
And you're set, the same goes with adding lighting effects to the object, transparancy, and more.
I deeply recommend looking into BYOND to see if your son is interested, I was hooked the moment I began but I've moved onto DBP now, though I still go back sometimes to see old friends on their games.
Linkage:
http://www.byond.com
With all these capabilities, after a month of practise you could literally make a full blown RPG with online play and chat, weapons, armour, monsters, quests and more in a day of hardwork.
Hope its been of some help, goodluck.
