Jamie, who lives on a small farm with a couple of horses, was used to collecting manure for his dad to use on the garden.
"That's how the idea started, we had our own pile," he said
Needing more, they approached The Farmhouse horse trek company who were more than happy for the boys to remove their manure pile.
Market research and discussions with garden centres have been positive but as with any business idea, there have been challenges.
One was finding a company to make the packaging - something the boys are "still working on".
The second was the recent wet weather which meant drying the manure has taken longer than expected.
"It's half dry - we're hoping for sun so we can take the cover off and dry it out," Jamie said.
They won't have the pellets ready to sell tomorrow, but they will be taking pre-orders and hope to have the pellets ready next month.
If the business takes off, the boys intend to continue developing it - but have back-up plans just in case.
"If this falls through I'll go to university," Jamie joked, while Sam plans to put his business skills to use as a chef or hotel manager.
JPC Young Enterprise Scheme teacher Minka Webb said the school had run the course for the past eight years and for the last two it had been an NZQA qualification.
That means students get NCEA credit for their work over the year - which involves a Dragon's Den, business and marketing plans, annual reports and product development and selling.
Ms Webb said the JPC students had been preparing for the markets for a couple of weeks.
"It's all very well selling to mum and dad and the neighbours but having to engage with real customers can be quite daunting."
Other JPC teams will be selling products including paper mache letters as name plates, solar powered iPhone chargers and clocks made from vinyl records. The market is on Tutanekai St from 5pm.
