Police are planning to crackdown on predators, particularly adults, who sell alcohol at inflated prices to school leavers at Rottnest and Dunsborough.
West Australian police have also urged parents not to buy alcohol for their children as they embark on the State's Leavers Week festivities.
More than 60,000 school leavers are expected to flood the traditional party spots of Dunsborough and Rottnest from November 26, and the State Government has just revealed it has spent $200,000 on support services for the thousands of revellers.
Commander Fred Gere said at a conference today, police were aware from alcohol being sold to leavers at inflated prices and there was evidence that it had occurred during past Leavers celebrations.
Police have also warned school leavers who are heading overseas to be mindful of the fact that different countries have different laws, warning that help could be a long way away.
Organisers of WA's Leavers Only entertainment zones say anti-social behaviour has decreased markedly in recent years, with a claimed 96 per cent reduction in the number of arrests in Dunsborough and the Busselton area since 2004.
WA Police project manager Scott Bermingham said parents buying alcohol for their children were asking for trouble.
"We ask parents and other adults not to supply their leavers with alcohol," he said.
"Research shows that young people who drink alcohol in an unsupervised manner consume alcohol at more harmful levels."
The $200,000 government grants are going towards support services focusing on excessive alcohol consumption, drug use, personal and community safety, unsafe sex and anti-social behaviour.
A $100 wristband available to leavers will allow them access to transport, rides and music.
More than 500 volunteers will be in place to support leavers from November 26 to 29.