Meryl Streep Before She Was Meryl Streep

Feb. 26, 2010 — -- An actress can be known for her emotional intelligence, her physical wit, her sensuality or her humor. She can be known for her versatility or her playfulness, or for her ability to deliver a dramatic monologue in pouring rain and not look silly.

Meryl Streep is known for being perfect.

As a Polish Nazi refugee: perfect. As a neglected corporate wife: perfect. As a single mom on a Greek island, dancing and belting out ABBA tunes: perfect. For her perfect portrayal of Julia Child in this year's "Julie & Julia," Streep is an Oscar nominee for a record 16th time.

But what about the early years, before Meryl Streep was Meryl Streep?

Watch "Before They Were Famous," on a special edition of "20/20" Tuesday, March 2 at 10 p.m. ET

ABC News recently sat down with two figures from Streep's past -- her best friend in high school and her graduate school drama coach -- to talk about the star's teenage days and her early stage career.

So what was she like back then? Pretty much perfect, it turns out.

"She was very outgoing. She had a great personality. Extremely funny," said Susan Castrilli, a friend of Streep's from Bernards High School in Bernardsville, N.J. "She was -- you know, I think the Meryl that you see now is the Meryl that was 14 years old. I don't think she's really changed all that much."

Michael Posnick directed Streep at the Yale School of Drama.

"It was just clear that there was something massive, monumental, really Himalayan about her work," Posnick said, "and about her gifts. And they're marvelous gifts. ... It's totally magic. There's a part of it that can't be explained. It's just an ability to become a character that represents a huge part [of] humanity. She's terribly human, wonderfully human."

Castrilli met Streep one summer day on the way to the pool. The Streep family had just moved to town.

"I used to cut through the woods to go to the community pool, and there was this blonde sitting on the porch there," said Castrilli. "It was a screened-in porch, and as I'm passing she looked up from a book she was reading. She said, 'Hello.' I said, 'Hello.' And she wound up at the high school."

Streep's given name is Mary Louise -- but she already was known as Meryl.

"Her mother gave it to her, actually," said Castrilli. "Her mother gave her the name Meryl because it was Mary Louise -- Mary L. She was named after her grandmother."

Meryl Streep in a cheerleading squad yearbook photo.As perfect as she was, Streep did have one failing, Castrilli said.

"Driving. I'm pretty sure that she kind of smashed up the driver's ed car, I heard," said Castrilli. "I know she smashed up the car once when I was with her. I had my license. She only had her permit, but her father gave us his beautiful, big car because we were gonna go driving around town like big shots, you know. And she wanted to practice.

"So he let me be responsible. The one with the license. So we're sitting there, and she's starting to go down a road, and she said, 'No, I don't want to go. I want to go back home and get something.' I said, 'All right.' So she just turned and hit the gas and BAM -- into a telephone pole.

"We got out, and there was this dent in the trunk and the bumper. And it was just awful. There was no way to hide it. ... When we went home, it was not a happy household."