So, it's been sooo long since I have heard that song that I had to look it up.
Great mnemonic device!
Just one little suggestion:
Change the word "Shoulders" to "Pebbles" and you have all seven words which use an "x" to form the plural.
Jewels, Pebbles
Knees and Toys (repeat)
Ca-a-bba-age
Lice and owls
Jewels, pebbles
Knees and toys!!
Or: You could try it in French:
Bijoux, Cailloux
Genoux, Joujoux (repetez)
Chou-ou-ou-oux
Poux et hiboux
Bijoux, Cailloux
Genoux Joujoux
Merci et Bonne Continuation !