I remember this being sung by two young sisters, Patience and Prudence. I hope this is the same song. Here's the chorus in the key of G. Sorry, I can't remember how the verses go.


It's

G          Em          D
summertime, summertime, sum-sum-summertime,
G          Em          D
Summertime, summertime, sum-sum-summertime,
G       D      G
Sum-mer- ta-a-a-ime!