I am trying to remember the title and author of a classic sci-fi short story / novella involving an alien invasion. It is difficult to fight the aliens because they use images designed to disrupt brain function and kill humans who look at them. In the story, one of the kids parents belongs to the government agency to study and counter these lethal designs. The kids get a hold of one of the designs, and repeatedly expose themselves to it in ever increasing lengths of time, building immunity. Anyone remember this? If I had a bet, I'd say I probably read it in The Road To Science Fiction or The Science Fiction Hall Of Fame series. Any help would be appreciated. Thank you!