A child’s brain processes certain stimuli best at certain times. For example, visual cues are best developed from the age of 2 months to 2 years. Then the door begins to close. If the brain does not get enough stimulation (due to cataracts or other problems), the brain may lose the ability to process the stimuli provided by the optic nerve, even if surgical procedures have corrected the original physical problem.
Children must have necessary experiences in a structured and encouraging environment. Language centers in the brain slowly close down between the ages of 6 and 11. This is why Challenger starts children learning language skills at 3 years. By age 11, their language arts skills are deeply entrenched.