My first TV show was one of the following... after all this time, they kind of run together in my memory:
1. Sesame Street
2. New Zoo Revue
3. Romper Room
I will add this: I grew up in the 60's and 70's. Back then, child-accessible TV was all about emphasizing good behavior, getting along with others, obeying your parents, all that. Not just the three shows above, but Prime Time programming was all about people getting along despite their differences, we're all the same under the skin, traditional family values, etc.
My point is: I BELIEVED IT. All of it. I still do; by the time I learned that the "real world" behaved differently, it was too late. I was always a little out of step with most, but not all, other folk because I didn't drink, didn't party hard, avoided premarital sex, etc.
I'm not complaining, though. I'm glad I grew up the way I did. I have a good life.