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          What would be a good one to buy today that would hold a young man's attention?

I would say don’t expect to hold a nine year olds attention for very long.  The normal rule is one minute for each year of age as my own grandchildren constantly re-remind me every times my plans for their scientific awakening go awry.  At nine, I was always buying plastic telescopes for pirate games etc, but they never seemed much good and usually got trodden on fairly quickly.  I got on much better borrowing grandma’s magnifying glass.  That always seemed to work, and you could burn holes in paper with it too.  I also had great fun with a 50x microscope which I saved up months for.

So I would say don’t buy anything too sophisticated unless you want to wait a few years to see it used to its full capacity (unless you want to play with it yourself).  DaveP