Taste always trumps nutrition!

Implications: Attracting kids to specific brands can set a pattern for future brand loyalty and purchases.
The key is to offer foods and beverages that kids like; that parents feel good about them buying, or buying for them; and that will meet the regulatory pressures that schools and other institutions increasingly are subjected to.
Kids intentionally reject foods that they think their parents want them to eat, unless they taste so good, or attain a high "cool factor" among their friends, that overrides the parental approval, urging, etc. 

Analysis: One disturbing trend relating to youth nutrition and obesity is the increasing consumption of high caffeine, high calorie drinks, especially the frozen drinks, offered at Starbucks and similar coffeehouses.  Why is this happening?? -- they taste great, they're sweet and filling, they provide a light "buzz", and all their friends are hanging out there.  The younger kids want to emulate the older kids, and there's a certain "cool" factor involved.
On a broader basis, food companies can and should provide healthier alternatives, especially for snack foods and "junk food", but the key to success is offering choices that are packaged to appeal to the segment and taste great. 
Look at the recent repackaging of milk products-- instead of the old milk cartons, for example, kids can now buy milk in packaging with terrific graphics, and that are easier to open, carry, re-close, etc.-- that are offered in different flavors, that have a certain novelty appeal.
Innovation in packaging, variety, taste profile--these are the qualities that will drive success in the kid's food and beverage market.  If these products also happen to be more nutritious, healthier, natural -- all the attributes that parents are looking for-- these are the products that will win the marketing and sales battles.