I'm a huge fan of the Uncle Mark Gift Guide and Almanac, published yearly by Mark Hurst, the founder of Creative Good. Every year (since 2003) Mark has assembled his guide to recommended books, apps, tools, events, and gadgets in the form of an attractive PDF file. Chances are good that you'll find several things in the guide that you will want to have or give to others.
DragonBox Algebra is a $6 iPad game that teaches kids a few simple patterns for manipulating colorful, friendly icons between two panels. The twist? Without knowing it, the kid is learning algebra. It’s brilliant. I recommend DragonBox and look forward to seeing more games that quietly teach skills and knowledge that kids can apply in the real world.