And thanks to Marco Kalnenek from previous blog, we discovered that there's a netlabel dedicated to kids: "Kazoomzoom".
From their website: "Kazoomzoom.com is the world's first netlabel devoted to children. Our little community is making history together! The netlabel features music for kids (by kids and by cool grownups), as well as audio stories, videos, printable books and paper toys. All of it is free to stream and download.
The Kazoomzoom website and content is all created and shared by volunteers. Nothing is being sold to children.
We encourage people of all ages to add their music, stories, art and other content for kids at Kazoomzoom.com. Illustrators, musicians, story readers and writers, toy makers and other artists choose whatever copyright system they prefer for their submissions, from full rights to public domain."

I certainly liked their "Silly Songs", "La Valise aux Mille Voyages", and " Our Corto Discorso ".

This is definitely recommended stuff for teachers and other people working with children.