Well...sort of. The spring spawning season probably provides the hottest Crappie action of the year.
But don't overlook the Fall! For folks in the northern parts of the U.S., crappies will strike flies and lures all the way to ice-up. They seem to move in close to shore again in the Fall, and hang around the last bits of green weedbeds and brushpiles. Its a good time to try catching some of the larger female crappies that were hanging out beyond your casting reach during the spawning season when the males were sitting on nests.
A slower presentation is often in order for this cooling water season. For folks using spinning gear, a 1/16, 1/32, or even 1/64th oz jighead tipped with a crappie-sized plastic tube jig body suspended under a small bobber is all you need. Adjust the distance between the bobber and the jig to fish over the top of the weeds and brush. Snagging on underwater obstructions is annoying, and crappies usually prefer to move up to strike anyway.
Fly anglers can use a microjig (1/80 or 1/100 oz) under a small strike indicator. I prefer the football-shaped indicators with the rubber core that holds the line in place.
I did really well late last fall with catching some nice crappies on flyfishing gear. I tried it during lunch today. Conditions weren't ideal, but I managed 3 crappies and a bluegill. I think its just going to continue to get better from here on until ice-up!