"Through a Voorhees was he born... through a Voorhees may he be reborn... and only by the hands of a Voorhees will he die." - Creighton Duke (Jason Goes to Hell: The Final Friday)
First you must find the remains of Pamela Voorhees and some other supplies : her head, her sweater, a shovel and the Necronomicon (same book used to make the infant Jason rise from his drowning death), all located at Jason's shack. A limitation could be one counselor can carry only one item at the same time. So you'll need four people to go to Jason's shack. Then you'll need to go to the cemetery where Pamela Voorhees is buried.
I'll think you must resurrect Pamela Voorhees through the usage of the Necronomicon and you can probably control her in the game like you can with Tommy Jarvis. Then you must strike Jason with a dagger/machete in his heart (beware Jason can still kill you as Pamela). I know Pamela Voorhees doesn't want to kill her own son, but maybe the Necronomicon gives you control over her in the same way as Pamela controls Jason, through her voice in his head.
Or maybe you can call up Jessica Kimble who dispite her last name is a Voorhees. She killed Jason off in the movie Jason Goes to Hell: The Final Friday.
All other methods will not work unless you could reverse the spell cast by Pamela Voorhees.
You could always try to blow Jason Voorhees to pieces but he will still return as long as his heart lives (see Jason Goes to Hell: The Final Friday)