"Paul Kierstead" wrote in message
...

Bottom line: Pine will work, pine is cheap, the end result will end up
dented and will sag a fair bit under load (though I am assuming a 7 yr
old doesn't have a large collection of heavy books). Otherwise, whatever
is the cheapest hardwood in you area is a good choice; for example,
around here popular often is more expensive then red oak, so it varies.

I was looking for a reason to use the sagulator. According to it, White Oak
and Eastern White Pine only differ by .04" in their sag over a 3 foot span
with an 8" board. Less than I thought the difference would be. Not that
I'm trying to make a case for using pine! I was just surprised at how close
the numbers actually came out.
--

-Mike-