How, and more importantly, why, did a Poconos teenager end up dead in a highway ditch over the weekend?  That's what friends and police are trying to figure out. 

An autopsy revealed that Corey Costenbader, 19, drowned after witnesses said he ran across a busy Monroe County highway -- barefoot -- and either fell, or jumped, into a ditch.

Exactly why Costenbader ended up there, though, is the subject of a lot of speculation.

Friends like Kimberly Desjadon spent the weekend searching for their missing classmate.

"I miss you Corey," she texted him on Saturday.  "I just want you to stay safe and warm.  Please come home."

Desjadon and others were searching for Costenbader, who went missing Friday night.

"Me and my mom went out and we were looking for him," she said.

Instead, searchers found Costenbader's body Sunday morning, submerged in a murky drainage ditch off Route 33 near the Monroe County Prison.

"None of his body was showing in this water," said Monroe Co. Coroner Bob Allen.  "He was submerged 100 percent."

Friday night, authorities said Costenbader was riding in a car that pulled off Route 33 north.  Witnesses in the car said he jumped out with no shoes on, darted across both directions of traffic, and appeared to have been hit by an oncoming car.  An autopsy performed Monday found the teen had not been struck, however.

"This young man drowned.  He had no other visible injuries at all," said Allen.  "I can't say that the car going by him didn't make him fall over or maybe you know made him try to get away from."

Costenbader's cousin has posted videos and a Facebook memorial page, where friends are still trying to piece together exactly what happened -- and why.  Allen said toxicolgy tests will determine if drugs or alcohol played a role.

"We will know for sure, but it will take at least two months," he said.

If they did, it's a surprise to Desjadon.

"He'd be like, 'Don't do that.  That stuff is bad,'" she said.  "He'd be like, 'Stay on the right path.'"

Friends at Pleasant Valley High plan to wear blue or black to school on Tuesday.  This is the second student death there in the past two weeks. 

Frankie Chester Lewoc was killed when the car he was driving went off the road and hit a tree, then the stone foundation of a barn in Chestnuthill Twp. on Jan. 5.

Lewoc's father, Chester Lewoc, was arrested over the weekend and charged with burning down a barn connected to the accident.