Students at St Paul's Catholic College in Greystanes have raised more than $10,000 in five weeks for Project Compassion.
It was the largest amount students had raised for the appeal to help fund the work of international aid charity Caritas Australia, which is supported each year by schools in the Parramatta Catholic diocese.
Encouraged by Student Representative Council members, the school's 800 students met their target of $8000 with two weeks until the appeal ended and finished with a total of $10,600.
"It was all just pulling out of their own pockets," religious education co-ordinator Aaron McDonald said.
"They didn't get a day where they could dress casually or buy cakes or that sort of thing, so it was nice."
Year 10 student Daniel Benton and his school council peers attended a Caritas-run workshop that detailed some of the projects the appeal supports.
He said the projects included Brazilian slums and remote Aboriginal communities.
"Some people aren't as lucky as us," he said.
"They don't have daily necessities like running water, and the money is going to help kids get an education so they can break the cycle of poverty."
Student Representative Council co-ordinator Roubica Akkouche said students were motivated by the workshop to donate.
"It really opened the boys eyes to where the money actually goes to," she said.
"Giving them a purpose is really important.
"They want to know how they are actually giving back to the community. It blew me away how generous they were."