My inlaws bought my son a Smithsonian brand microscope and several microscope books for his last birthday. He loved it even though it didn't work at all. The microscope books were awesome, but the scope itself was very poor quality and I couldn't see anything through it, except for on the lowest magnification in a rather blurry way.
Anyway, we're looking into buying him a working microscope for his coming birthday. I'd like to get one that is not a cheap plastic toy, but that isn't too expensive (under $150 hopefully). Any recommendations?