If the recession has been as hard on Madison Avenue as on other sectors, a lot of marketing types are probably free to watch daytime TV. And if marketing’s your game, that’s time well-spent. You can surf the kiddy shows and learn from the true masters of your art: environmentalists.

Their latest coup? Elmo, the most popular character on PBS’ “Sesame Street,” has gone “green.” Literally.

The environmental left has accomplished what marketers dream of: hooking consumers from a young age and creating customers-for-life.

What’s more, they’ve done it on the cheap. As CMI has documented, Nickelodeon’s “Big Green Help” gives valuable web resources, ad time and talent resources to getting kids to “pledge” to take carbon-reducing actions and to annoy their parents into taking them too. Just last week, Nick used valuable airtime during its “Kid’s Choice Awards” to bestow the “Big Green Help Award” on actor Leonardo DiCaprio (who’s probably as relevant to today’s 10-year-olds as Clark Gable).

Having already conquered the preteen market, and emboldened by evidence that it’s made important inroads with adolescents, the Gaia Conglomerate has scored the ultimate product placement victory – for free! The traditionally red Elmo was literally “turned green,” in a new “Sesame Street” DVD called “Being Green” to teach preschoolers about all environmental pieties.

Sure, PBS and the Sesame Workshop are likely candidates for environmental marketing. If you want to sell beer and salty snacks, go to ESPN. If you want to sell environmental awareness, you go to the one-worldy network with an audience of future community organizers. But getting Elmo on board is no less genius for all that.