My son is 5 and knows his phone number (I taught it to him in song form and he learned it easily!). My other son is 3 and doesn't know it. I think he'd say my name is Mama if someone asked him (even though he's been known to call me by my first name a couple times). Neither knows their address, though I've been working with my 5 year old on it. He remembers the street and the state but gets mixed up on the city and doesn't know any of the numbers.