Simple Past/Past Continuous

Last night, while I was doing my homework, Angela called. She said she was calling me on her cell phone from her biology classroom at UCLA. I asked her if she was waiting for class, but she said that the professor was at the front of the hall lecturing while she was talking to me. I couldn't believe she was making a phone call during the lecture. I asked what was going on.

She said her biology professor was so boring that several of the students were actually sleeping in class. Some of the students were talking about their plans for the weekend and the student next to her was drawing a picture of a horse. When Angela told me she was not satisfied with the class, I mentioned that my biology professor was quite good and suggested that she switch to my class.

While we were talking, I heard her professor yell, "Miss, are you making a phone call?" Suddenly, the line went dead. I hung up the phone and went to the kitchen to make dinner. As I was cutting vegetables for a salad, the phone rang once again. It was Angela, but this time she wasn't sitting in class.