I really don't remember with any but one of my kids. Her experience stands out for me because I had no idea she knew anything about telling time. When she was 3.5 I gave her the CAT5 assessment for kindergarten. She easily answered all of the time telling questions in the math section, indicating that somehow she had figured it out on her own. I'm pretty sure the questions were to the hour and half hour only, but still, I was impressed.