I was slightly too old to watch either Romper Room or Ding Dong School, but my sisters really liked it.
Family anecdote: We had a local kid's program called "Kindergarten College" that featured a few kids sitting at desks and acting like they were in school. The kids were there for one week.
For some reason, one of my sisters, who was five at the time, was picked to be on the show. Unfortunately, at the time, she was absolutely obsessed with bras. Nobody knew why, but she was. She would cut pictures of bras out of catalogs and paste them into a scrapbook. And she talked about them a lot.
The night before her first session, Mom sat her down for a stern talk. "Now, _________, we aren't going to be talking about bras on television, are we?" My sister looked her in the eye and chirped, "Oh, no, Mommy! I wouldn't do that! It wouldn't be sanitary."
That became a family catch-phrase that exists to today: "Oh, don't do that! That's not sanitary!" It applies to about everything.