I made this beautiful experience in an Italian school. More than 100 children were divided in 2 groups: 2-3 yrs old and 4-5 yrs old. I made 2 little gigs for them making them try the theremin.
Amazing! I gave them many other musical instruments too: guitars, dulcimer, percussions and many other strange or common things that they used to make a little orchestra playing with me.
The music must be in the school system!