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This may not give the level of precision you're looking for, but it's
simple and easy for kids to understand:  Make a quadrant out of
cardboard.  Print the protractor with a laser printer, either directly
onto light cardboard, or onto paper that you glue to heavier
cardboard.  Make sure the zero is parallel to one edge of the
cardboard.  Cut around the arc so you have a quarter-circle, or a
half-circle, or something in between.  Poke a tiny hole exactly at the
vertex, and insert a thread.  Tape it in place on the back, and tie a
weight (I used washers or nuts) so the thread hangs taut just below
the arc.  Tape a drinking straw along the edge of the cardboard for a
sight, so it is supported by the edge like this:  O==  To sight stars,
you look through the straw with one eye, and around it with the other,
and place the star at the center of the circle.  Rock the quadrant
until the stationary thread just grazes the cardboard, pinch it in
place, then read it.  You should be able to read to 15' or better with
a reasonable-sized scale, though your sights will likely have more
scatter than that.  For the sun, don't look through the straw --
instead, watch the quadrant's shadow, and point the straw at the sun
until its shadow becomes an "O".  Again take care that the quadrant is
in the vertical plane, and pinch the thread.  (This measures to the
center of the sun, not to either limb.) You should check each quadrant
for index error -- assuming your printer is properly adjusted, and the
thread pivots in the center of the arc, other errors should be
negligible.  Good luck!
    -- Bill

On 11/27/07, Isonomia  wrote:
>
> I'm camping next summer with a load of 11year old kids and wanted to
> do some celestrial navigation and plot a position to within
> 10-20miles.

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