This advice is good or bad depending on the style of your nephew. If he is really exciting about programming, then he most likely has in his head this idea of hacking away at physical lines of code rather than Alice/Squeak/Scratch.<p>I'd suggest BlitzBasic in companion to the fantastic book Game Programming for Teens (<a href="http://www.amazon.com/gp/product/1598635182/ref=pd_lpo_k2_dp_sr_1?pf_rd_p=486539851&#38;pf_rd_s=lpo-top-stripe-1&#38;pf_rd_t=201&#38;pf_rd_i=1592000681&#38;pf_rd_m=ATVPDKIKX0DER&#38;pf_rd_r=1BH53J6HZSR8Q81T82Q6" rel="nofollow">http://www.amazon.com/gp/product/1598635182/ref=pd_lpo_k2_dp...</a>). Blitz is cross platform, extremely easy to dive into, and has a great graphics library. Or, if you want to start him out pure, I'd suggest python/pygame.