"Linus and Lucy" (Vince Guaraldi Trio)

Before writing the classic "Linus and Lucy," pianist Vince Guaraldi had a fairly big hit (especially for a jazz single) with a song called "Cast Your Fate to the Wind."  It is very much in the same instrumental vein as "Linus and Lucy," featuring upright bass, drums, and piano.  And, just like the latter, it has Guaraldi's singular approach: funky and swinging, yet bubbling over with this ebullient energy and childlike innocence.
So it's no wonder why Lee Mendelson, producer of Charles Schulz's Peanuts Christmas special, commissioned Guaraldi to score the TV program after hearing "Cast Your Fate to the Wind" on the radio.
I still marvel, though, at how funky "Linus and Lucy" is--especially that last bridge before the final chorus, and yet it still perfectly captures the innocence of childhood.  
But that's why I love this song.  It isn't some saccharine, watered down kiddie pop that was crafted by studio executives and hired hit-men to be an instant hit single the minute the show originally aired.  The composition has real grit and integrity, and it stands on its own as a great composition.  
At the same time, it captures the spirit of running around with abandon but also falling down and skinning your knee.  In fact, it's the whole wild wonder of being a kid, condensed into 3 minutes.