Woolly worms, foam spiders, hares ear nymphs, and pretty much any other trout fly can be used for 'gills.
for bass, poppers and clowser minnows and a worm fly called a Gully worm.
Crappie, anything that immatates a minnow seems to work, clowser minnows, woolly buggers ect.

alex pernice you spelled clouser wrong but on another point i like fam poppers for gills and clouser minnows for crappie

Only here can you get a well rounded education!

You could tie a cigarette butt to a hook, then on your line, and cast it out. Let it sit for a couple of seconds, twitch it a couple of times....And you got yourself sunfish!

3 layered foam sandwich hopper with silly legs in sizes 10 and 12 will slay the 'gills and sunnies all day long and into the evening. Brown and olive is my go-to color, but red and yellow have also performed well. I also drop a small wooley bugger (usually hot and flashy, e.g. cactus ice olive, pearl, or chartreuse) a couple feet under the hopper to cover the water column in and give offering options. It’s especially handy for enticing bass, which often prefer the chase over the ‘gills, who prefer to come from behind, investigate and then strike a near non-moving fly. Keep the butts and tails short to avoid short strikes and niblers. Great fun on a 4 weight!

Down here in alabama I tye a pink producer
it works very well for my friends and I.
Take a #12 or #14 hook,put on a brass beadhead then tye on some thin pink chinele, wrap it forward to the beedhead, tye on two black saddle hackles and wrap right behind the bead forming a collar,whip finish and your done.
The #12 catches more bluegill but the #14 seems to catch bigger gills, I havent figured that one out yet!
Sometimes bass will hit it too.
Roger

wooly worm for sure

I think if I was going to fish for crappie, I'd throw a small, standard jig found in the spinning/hardware dept. You could throw a 1/16th oz. or a 1/32 oz. I know my big, black leach pattern works for smallies. A white one should be dyno-mite in the cold water months. And for poppers I use the industrial window backing tube foam found in the building supply stores..think they call it "Rod backing" Comes in grey, and white. I buy the white as it now will take color if I want to die them. I tie them as a tube fly tying what skirt I want onto the tube..makes for a big popper that is light wt.,no need for a big hook, just a stinger hook stuck up in the end of the tube, and you can throw them easy on a flyrod. Put eyes on the foam if you want..awesome looking in the water. I'll probably go to bed tonite seeing one "popping" across the surface.