An Ocean Theme concert is adorable for preschool, kindergarten and primary grades. A teacher using the Songs of the Sea book asked if 10 Fish in the Sea is a good song for Orff for Preschool. Since this song has a chord change, I would say no. You could play on the numbers on Cs but thats expecting a lot from little ones and it really wouldn't be fun for the kids or the teacher (too much to ask, too much structure). This is something I usually accompany (guitar, ukulele or piano or some teachers use the instrumental Songs of the Sea CD) and have them play unpitched percussion, playing on the numbers, lifting their instrument high over head when they sing high, next verse do some circular motion with the instrument without playing, last verse bending knees to go down low with a low voice. This is super cute with high voice, low voice and playing on the numbers. Rhythm sticks (my little short ones) are successful for even the youngest 2 and 3 year old classes.http://musicrhapsody.com/product/rhythm-sticks/
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