The school is taking this very seriously even though these incidents happened off campus. The principal says so far at least three senior girls were contacted, and there could possibly be more.
"This is the item he left my daughter in the Walmart parking lot, underneath the light," said one mother. "He left her $100 cash and another letter."
This mother says a strange man repeatedly messaged her 17-year-old daughter on Facebook, promising money and gifts, and even asking her to meet him.
The victim, Jaci, admitted, "I was interested because he offered me a $10,000 scholarship. You just don't get opportunities like that."
She is not alone. Administrators at Crosby High School have at least three reports of the same man offering the same things to other 12th grade girls.
"I've gotten messages like that before, but I just block them," said one girl.
Principal Greg Bower sent an automated message to all parents at the high school as a warning.
"Recently a couple of high school students have received private messages from an adult stranger," he said. "Whether it be Facebook, Twitter, Instagram, Reddit, or whatever, I think (parents) need to know they need to monitor those accounts."
Parents we talked to were on edge.
"I talked to them and said they need to only accept people that they know and not trust everything that they read on there that people say they are," said one mother.
Jaci's mother tells Eyewitness News the school and the Harris County Precinct 3 Constable's Office have offered her daughter security on campus, and a designated parking spot.
The man in question hasn't been arrested or charged. The school district says the investigation is ongoing.
Take ABC13 with you!
Download our free apps for iPhone, iPad, Android and Blackberry devices