Re: lead testing

You can obtain several kinds of lead test kits at local hardware, home safety,
or discount stores.  Most of these tests change color and  will tell you if lead
is present, not how much lead is present.  Normally, these tests are used to
say  no it is not present" OR " it should be tested by a better method".

Lead is checked by either chemical testing at a lab or by XRF (X-ray) testing
in the field.  An XRF instrument costs $15,000-25,000 and takes training.  The
chemical test can be done with a spoonful of paint chips for  $8-10 each.  If
you have tests done, the results will tell you if it is lead based paint.  The 
cutoff is 0.5% lead.  Call the EPA hotline number at 800-424-LEAD for info
and booklets.

For a science project, you could test several neighborhoods with the test kits
to see where lead may be present.  As a licensed lead inspector, I can tell
you to check the windows, especially outside, porch columns, etc.  Walls are 
not usually painted with lead paint.