Look carefully on the right side of the screen in the scene where Laura and Albert are painting Mary's house. There are a couple of moments where you can clearly see one of the microphones come into view of the camera and then go out again.
Nitpick: Why would the mercantile stock enough purple and pink paint to cover a house? Colored paint wasn't readily available, or widely used, until the 1930's, with the exception of in ornate buildings like hotels and churches. In the 1800's wallpaper was the wall cover of choice; in fact, it was a status symbol. Whenever a painted surface was shown in Little House, it was almost always white.
Goof: the opening scene, Mary is quizzing her class about historical dates. As the children are answering her out loud, you can hear at least two of the boys shout answers like "1903." This is obviously impossible, given the fact that the show was set in the 1800's.
Notice the scene right after Caroline gets the saddening telegram about Mary, and Alice Garvey is hugging her. Laura and Albert come barreling in to tell their Ma about the house they have finished, and they stop cold when they realize she is crying. Melissa Gilbert (Laura)'s stunned, upset facial expression is perfect for the scene and the situation, but notice that Matthew Laborteaux (Albert) almost looks like he's about ready to laugh.
It's interesting to note that in less than one year, Mary has gone blind, gotten married, became pregnant and miscarried, and found out that she might be regaining her sight, only to be disappointed--and these are the most minor of the problems she faces in later seasons!
Goof or Trivia? Ruth Foster plays two parts in adjacent scenes, Matilda then Mrs. Foster (her character's first name is also Ruth).
Charles: Well, I think the first thing you ought to do, starting right now, is start being honest with yourself, and stop pretending that it's Adam you feel sorry for.
Mary: But it is.
Charles: You're not feeling sorry for Adam. You're feeling sorry for yourself. I can't say I blame you, but quit lying to yourself about it.
Mary: I'm not! It is Adam.
Charles: It's Adam, huh? All right, if you had a choice...if you had a choice, and only one of you could see again, who would you pick?
Charles: You heard me. Who would you pick? Would you pick you or Adam?
Charles: Oh, come on, Mary, you'd pick yourself, and you know it! And you wouldn't be doing it for Adam! In the name of God, just say it one time. "I wanted to see again for me." Say it. "I wanted to see again for me."
Mary: (pauses, starts crying) I wanted to see again for me. I wanted to see again for me!
Mary: (when Laura hugs her and starts crying) Hey, now. What's this all about?
Laura: I was so sure you were going to see again. I was just so sure.
Mary: I know. I was, too. It's a good lesson--never count on anything until you're sure.
Laura: But I wanted you to see again so bad. I wanted you to be able to do all the things you planned to!
Mary: All right, now! That's enough. Are you feeling sorry for me or for you? Listen, I'm the one who's blind here, all right? And you better get used to it, because that's the way it's gonna be. Laura, before I went blind, I wanted to teach. And well, I'm a teacher. I had a wonderful family. I still do, plus a wonderful husband, and a sister that I love very, very much.
Mary: I smell paint. I thought this was the old Edwards place.
Laura: It is.
Mary: Well, who on Earth would want to fix up a place like this?
Laura: Oh well......Albert and I thought it would make a neat clubhouse.
Mary: Oh. What colors did you use?
Laura: Pink and purple.
Mary: (scrunches her nose) Pink and....purple?
Mary: You know, Laura....I'm kind of glad I can't see it.