Our whole family takes Omega-3 supplements. For kids, a company called Northwest Natural Products makes L'il Critter Omega-3 Gummy Fish that taste yummy - DS and I both take these (DH takes a GIANT fish oil capsule - ugh!). For DS, it does seem to help him focus and for me, I notice an improvement in my ability to learn and retain faster (especially physically - I'm a dancer).

I also throw flax seed into our homemade bread, and we put milled flax seed into our pancakes and baked goods.