If you're new here, you can see songs 46 through 50 here.
And there's still time to enter the contest.
On to songs 41 through 45...
45. "Fee Fi Fo Fum" - Ralph's World: There are many great Ralph's World songs, but this I think this song is likely to stick around, combining simple lyrics ("It doesn’t matter what you look like if you got some Fee Fi Fo Fum / It doesn’t matter what you look like and let me tell you everybody got some") with an infectious melodic line. It will make for great covers many years from now. (Listen to the whole song at Ralph's music page.)
44. "Conjunction Junction" - Bob Dorough: The whole Schoolhouse Rock! series was a flash of inspiration, trying to use the medium of advertising to hook kids on learning. This song, like so many others in the series, took complex subjects and rendered them instantly easy to grasp. The cartoon visuals are fabulous, of course, but even divested of those visuals, tracks like this one are still models of songwriting thirty years after they were first written. (Listen to samples from the orignal show here.)
43. "Muffin Man" - traditional: Do you know the Muffin Man? The Muffin Man? On Drury Lane? The basis for a joke in the Shrek movies. Unsurprisingly, the song comes from England. In researching this entry, I learned that Frank Zappa sang a version of the song. The Ralph's World version I suspect is more conventional, but it's got a fun energy nonetheless. (Listen to a sample of Ralph's version at Ralph's music page.)
42. "Frog Went Courting" - traditional: In his liner notes to his We Shall Overcome: The Seeger Sessions disk, Bruce Springsteen says this song can be tracked back to (at least) a Scottish tune from 1549. It seems to me that any song that gets recorded 450 years after originally written deserves some sort of spot on this list. (Besides Bruce, Bob Dylan, Elizabeth Mitchell, Dan Zanes, and scores of others have recorded the song. Here's a Pete Seeger version.)
41. "Rubber Duckie" - OK, my all-time Sesame Street performance is R.E.M. singing "Furry Happy Monsters," but I'm pretty sure that this song here will be sung many years from now. It has a timeless ragtime feel. If only I could find a rubber duckie that squeaked like Ernie's. (I'm not gonna post a listen link, because the one I'm enjoying now is squeaking past copyright law. You're smart. Google it.)