Anglican Family Care spokeswoman Lucy Summers said at the start of this term, 27 groups of pupils from St Hilda’s Collegiate were given $5 each and challenged to find ways to "grow" the money over the term.
The proceeds from the challenge would be given to the social services agency to continue its work with children and families.
Yesterday, the charity was given a $4500 return from its initial $135 investment, an increase of better than 3000%.
"We were totally blown away — it’s amazing," Mrs Summers said.
Year 13 pupil Meg Kinney (17) said her group held a "breakfast club" to raise funds during the term.
The group members made porridge and hot chocolate to sell from the archway at the school on Wednesday mornings.
The people buying the hot food on the cold mornings were pupils, staff and people passing by on their way to work.
As the cash flow increased, the group added hash browns to the menu.
The final breakfast on Wednesday was marketed as a "big breakfast bonanza", with an upsized menu including bacon-baps and waffles.
The 17 members in the group, between year 7 and 13, after paying for expenses, had about $700 to give the charity.
Meg said the fundraising was enjoyable because customers were happy to part with their money for comfort food.
"It was nice to know the money you were getting was supporting something which would be good for the community."