I just found this site because I looked up Ifca's Castle. I learned the song in Kindergarten in 1958, we sang the chorus as a round:

Above the plain
of fruited grain
a young boy's head
is plainly seen

A hooya hooya hoo ya ya
swiftly flowing rivers
a hooya hooya hoo ya ya
swiftly flowing rivers

But note is not
his lifted head
tis Ifca's castle spires instead

A hooya hooya hoo ya ya
swiftly flowing rivers
a hooya hooya hoo ya ya
swiftly flowing rivers

Those were the only two verses we were taught