Felix Paw, a precocious 3-year-old, has a favorite phrase: “I don’t know.” Which isn’t entirely true, as his mother, April, knows. He loves to quiz her on his favorite dinosaurs and sea creatures, congratulating her when she answers correctly and, when she doesn’t, wagging his little finger. Beyond the prehistoric beasts that once roamed the plains and the turtles that once swam the oceans, he’s beginning to learn letters and numbers — well enough that he reads off license plates at stop lights. And this week at Akron’s downtown library, Felix and his mom worked through large-print books.