the 3-9x40 size would be my suggestion. As for brands, wow, does that open a can of worms.
Some I've had in that price range that I would have again:
These just to name a few.
Some I've had that I would NOT have again:
Any of the no-name cheapo crap
The suggestion to check out SWFA's sample list is a good one as is keeping an eye out on the trading post here.
Pay it forward - Kids are the future.
Rifles are similar to boats and young women...there's no end to how much money you can pour into them without making them any more useful.