Is that Zuzu's teacher? Yes.
3 seconds sound clip from the It's a Wonderful Life (1946) movie soundboard.
You can hear this line at 01:29:16 in the Blu-ray version of the movie.
Quote context
[...]
- Hello? Yes, this is Mrs. Bailey.
- Oh, thank you, Mrs. Welch. I'm sure she'll be all right.
- The doctor said that she ought to be out of bed in time to have her Christmas dinner.
- Is that Zuzu's teacher? Yes.
- Hello. Hello, Mrs. Welch? This is George Bailey. I'm Zuzu's father.
- Do you realize she'll probably end up with pneumonia on account of you?
[...]