Perhaps kids who are progressing from Spyro and other cutesy platformers would enjoy Undercover, a long and flashy game they can coast through without frustration or effort. But anyone who's ever owned a wheel peripheral will find it too low brow to tolerate.
Bottom line: Need For Speed: Undercover contains all the components to make the next installment of the Fast and the Furious franchise. Unfortunately, that doesn't make for a decent game.
Recommendation: Leave it. Unless you're looking for a stepping stone between cutesy platformers and real racing games, the only challenge this game offers is perseverance.