The school said teachers have talked to their classes about safety, with a strategy for parents to create a "safety password" with their child.
"If they are approached by someone and given this type of message - they can reply - okay what is our password?" the statement said.
On Tuesday, two boys from St Patrick's School were approached by a man asking them to "hop in" his car about 3.10pm.
The school said the boys luckily exercised good judgment and school staff were informed.
In a statement, the school encouraged students to "be vigilant", while parents were asked to discuss stranger danger with their children.
"Our community constables will be increasingly present in our area over the next while," it said.
Police said they were aware of both incidents and local staff had been in contact with the schools to provide safety advice for students.
"There will be increased police patrols around these schools as a preventative measure," a police spokeswoman said.
Inquiries are being made to identify the vehicle, person or persons involved in both cases.