EVERY FATHER is supposed to teach his kids to fish. We're supposed to expose them to the delights of nature and the shared joy of landing a bucketful. But nobody ever talks about the kids' responsibilities in the matter.

Take girls, for instance. I have a couple of them, and about the time they got big enough to swim we set out to learn to fish. I was learning along with them, because I'd forgotten what little I'd learned about fishing as a boy (my father was a West Texas plainsman whose interest in fish, in the water or on the table, was severely limited).

Karen and Laura and I did just like it says in the outdoors magazines: We started out with cane poles and worms and went on to spincasting rigs. We worked our way through stinkbaits to crankbaits. We fished farm ponds and various sections of the Potomac, Rappahannock and Shenandoah rivers, and went surf- fishing during vacations. I think we also went deep-sea fishing on headboats, but I'm not sure of that because I get so seasick I tend to repress all offshore memories).

And, of course, there were the age-old lessons to be learned: that newcomers must be gentled along, because fishing requires patience and skills are not acquired in a day or a month; that fish shouldn't be counted before they're in the boat; that anger and tears have no place in the art of angling; and that sometimes you can do everything right, and do it all day long while maintaining a positive attitude and a reverent spirit, and still Mother Nature may send you home empty-handed.

At length the girls tired of trying to teach me these things, and shifted their attention to soccer. Karen suggested that I pick on her brother Mark, then five years old. "He might think it's cute to see you kick rocks and throw your rod at the water," she said.

His mother tried to shield the lad, but I winkled him out of the house one Saturday morning while she was painting or plastering or something, and soon we were sitting on the rocks near Fletcher's Boat House, soaking up the early spring sun and drowning worms in a muddy and floody Potomac.

Fully five minutes went by, during which he lifted his hook out of the water no more than 50 times to check it, before Mark grew bored.

"Here," he said, handing me his pole. "I'm going to go catch some fishes." He wandered off.

"The only way to catch fishes is to keep fishing," I called after him, reeling in my line again to check it. "You are acting like a child."

Mark had headed upstream, so I figured he'd float by if he fell in. After an hour or so, mindful of his mother, I went looking for him. He was lying on his belly with his right arm up to the elbow in the swirling, opaque water, and he was all covered with mud and ick. The ick had come from the score of sunfish,or bream or bluegills or whatever you call them, that were gasping their last on the ground around him. While I watched, he lifted yet another one from the water, the fish lying quiet in the curl of his fingers until he laid it on the ground.

Soon I was all covered with mud too. But not with ick, because the ick would have had to come from my fish, and although I tried to follow Mark's instructions, the fish would not "noogle up in your hand and you lift them out." All I got was a numb arm.

Nearly eight years have passed since that morning, and I have learned not to tell the tale to strangers, because it seems to offend them. Now I save the story until after the listener has spent some time fishing with Mark, or rather watching Mark catch fish, because the only way to get one when he has a line in the water is to foul-hook it as it's dashing for his bait.

This spring I've abandoned the shreds of my pride and outfitted myself with exactly the same rod, line, lures and bait as he uses. I've stood in his shadow and cast where he cast. I've studied how he cranks in his baits and how he responds to a twitch on the line.

He says I'm coming along nicely, and may catch my first fish any day now. Meanwhile, as always, we're eating his.