Introducing new instruments

Some instruments are easier to learn and play than others.  Some instruments are going to take some time to learn.  It would be developmentally appropriate to introduce the rhythm sticks and the cymbals early on in a child's life.  You could give a child these instruments at a very early age even before they understand what a beat is and how to keep a steady one.  They can just play around with these instruments to get a feel for music although they don't truly understand music.  When they go to school, they would know what a beat is and they could use these instruments to keep beats.  A kazoo is also a simple instrument that could be used early on.  To play a kazoo, one must hum into the instrument rather than just blow to make noise.  This would not be too hard to teach children in the younger grades because they would get the hang of it pretty quickly and could add vibrations to music.  The recorder and the xylophone are two instruments that I would wait to introduce to students until they are in the fourth grade or so.  I think this would be an appropriate age because at this age, children should know more about music and know what the notes are.  They should be able to read music and play songs at this point in time.