From the unhelpful department:1. A Mighty Fortress2. Self Esteem is For Everybody http://www.youtube.com/watch?v=CswwaOG01MM&feature=relatedAnd doing both back-to-back might open up a rip in the space time continuum...
I prefer the extended version. http://www.youtube.com/watch?v=a6VuhEnd4IM&feature=related
From the slightly daggy but fun department...(I'm not certain of the actual event you have in mind for the farewell song.)For my daughter's year six graduation they sang an adapted version of the Proclaimers "I'm on my way" something like "We're on our way from primary school to [ ] high today..."They had fun singing it.
Time of your Life - Green Day.Probably been done before.Nice if you have a child who can play the cello.
My Chemical Romance: SingFirework by Katy Perry
I shouldn't comment since I have no suggestions. But I did think Nathan's suggestion of the Pacman theme on Facebook was amusing.When I finished Year 7, I remember we all sang a very bad version of "I Still Call Australia Home" substituting the name of our school for "Australia." It was memorable though :)
'So long, and thanks for all the fish.'
Oh you Gary Ware, always the joker...