A 17-year-old girl attacked by a sexual predator while walking home from school is warning other students about the dangers of wearing iPods.

The teen is one of two St Mary's College, Auckland, students grabbed by strangers while walking to and from school. The second was barely a week ago.

Both were listening to iPods via earpieces at the time and did not hear the men behind them.

The 17-year-old, who did not want to be identified, warned others to turn down the volume on iPods or to wear only one earpiece so they were alerted to potential danger.

"It's something nobody ever talks about. People from age 12 to my age think they're invincible," she said.

In March the teen was on Hamilton Rd, five minutes from home, when a man came up behind her and "tried to grab me and drag me into a driveway", she said.

"I got such a fright. I screamed and shoved him and told him to f*** off."

The man - whom she described as stocky and of Pacific Island or Filipino origin in his 20s - then took off.

On June 23, a 12-year-old girl from the same school fought off a man's advances with a kick to the groin.

She was walking along Douglas St in Ponsonby when the man came up behind her, made lewd suggestions and grabbed her arm.

Police described the man as in his 40s with long silver or grey hair and with an orange hue to his skin.

St Mary's College principal Sandy Pasley said students and parents needed to be aware of the dangers of wearing iPods, especially when walking alone.

Following the second incident, she sent a newsletter to parents warning them about the dangers and encouraged students to walk in groups if possible.