Most art catalogues carry AMACO glazes which indicate which ones are lead free. You can also underglaze and the coat with a clear transparent glaze. However you can also have the students burnish the whistles and thus avoid glazing.
> I am planning to do a unit on clay whistles and am concerned about
> glaze safety since the whistles are being placed in my student's
> mouths. I'm looking for ideas on what might work for middle school aged
> students that could create fine details.Any ideas?