Just because your choice is Dora and Thomas and Yo Gabba Gabba and about 10,000 other toddler shows around the clock doesn't mean you should let your child tune in 24/7. In fact — brace yourself —experts say children under two shouldn't watch any television. (Yes, you read that right.) The reason: Those first two years are critical to a child's mental development — and it's too easy for a toddler to zone out in the presence of TV instead of being stimulated by new experiences.
If you absolutely can't imagine no TV, keep the viewing time down to 15-minute increments. And, after he turns two, continue to limit him, maxing out at one hour a day — if that.