I think its a great gift for a nine year old if you have time to support them with it. A Pi, a box and an SD card...okay, what about a keyboard, a mouse, a HDMI ready monitor or extra $s on converting that signal to VGA or whatever.
It would be an extremely rare nine year old who could be 'let loose with it' that would actually get anything out of it.
If you want to get him into programming can I suggest the EV3 materials from Lego? More expensive, granted.
I have both by the way!
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