Hey Brian! that's such a hoot!!!!
And seniorn@duke.usask.ca ~ I was just wondering about the why of your request. In almost every context I can think of: school, camp, etc., &c., it would be more appropriate to learn|teach|perform an actual French song, from France or Canada. No offense intended; I am second-guessing your intentions and purposes. I simply feel that if you want to impart a real feel for another language, honour it and its associated culture ~ do V'la le bon vent or Alouette rather than translating such thoroughly English rhymes as Farmer in the Dell.
Whatever you do and are doing with music, you WILL be back @ the Mudcat Cafe. More power to you in finding "Down by the bay", and so on. You could feed the lyrics into any of a zillion translation utilities available online, then a francophone on campus to help polish the machine translation to the requisite metre [blah blah blah .....] Children's librarian/music therapist/mudcat junkie.