I would start with the general tune up stuff (cap, rotor, plug wires, points, plugs, vacuum leak, etc.) It's kind of odd though that it idles OK and misses at higher RPM's though.
If you check the basic tune up stuff and all that is OK, then I would start some more serious testing with the ignition [sounds ignition related to me based on your limited info.] Maybe a bad coil or the + and - terminals are reversed?
I've also seen blown power valves cause some weird symptoms. I'd double check float levels and also check for a clogged fuel filter. I've seen bad fuel pumps cause problems like yours too.
If the ignition system and carb check out good then maybe you look for the mechanical problems like a broken valve spring, bad head gasket, etc.