Your Little League coach probably didn't know it, but every time he sent you to the plate with the instructions "keep your eye on the ball," he was giving you an impossible task.
And if you followed the coach's advice of positioning yourself directly under a popup, you probably struggled to catch balls in the outfield, too.
Myth: A left-hander shouldn't play catcher
I have seen a few left-handed all-star catchers in youth baseball. They had no trouble throwing out runners trying to steal second base. In fact, their throws were often better than right-handed catchers. They had no problem catching a runner trying to steal third base. Catching the low outside pitch was easier for the lefty, who is catching with their right hand. A righty has to catch the outside pitch backhanded, which a number of kids drop or miss.
You may not see a lefty catcher in the big leagues or college, but there shouldn't be an issue having a left-handed kid play catcher in youth baseball.
Lefties often have a easier time fielding bunts and making the throw to first base - this is especially true in softball were there are lots of bunts. The starting catcher for University of Washington national championship softball team in 2009, Alicia Blake, is left handed.