"I hope we've got enough sausages," she laughed.
Oueroa School was the latest in a string of rural schools to shut the doors - a victim of falling rolls as well as increasingly stricter building regulations which had begun to emerge in the wake of the Christchurch earthquakes.
When she started four years ago the roll was 14, and fluctuated as new entrants arrived, and established families either left or moved their children to town schools.
The rolls had once reached the thirties, as several of the photos on display at the function illustrated.
But, as Mrs Middleton said, times had changed.
She knew from the day she started, after arriving from Parkvale School in Hastings, that the future was uncertain.
And she knew that for sure at the start of this year when the roll had slipped to just nine.
"If one family with children at a town school leave the area, no one notices, but when a family at a country school leaves, then you really notice it."
She and Nicki Harding, who stood in as reserve principal and had been involved with the school since 2001, learned at the end of the first term that the school was earmarked for closure.
"We knew it was closing but didn't have a date - the ministry then provided that - Friday the 13th," Mrs Middleton said as she pondered her own future.
"It is sad, but inevitable." While it was sad to see the school go, yesterday's gathering was an effervescent one.
Youngsters who had since enrolled at other schools arrived and many gave Mrs Middleton a hug.
"Yes I'm going to miss her," five-year-old Reaynah Garret said.
"I liked it here because we got to do some handwriting and drawing."
Six-year-old Darryn Lawrie, who now attended Sherwood School, summed it up for all the children when he said, "it's just a neat school.'
Ian Schicker had plenty of good memories, having driven the school buses in the area for about 20 years.
"I brought the school's new toilet block out here in 1966 on the back of a a truck - we put some planks down and just slid it down right into place."
There were plenty of memories and stories swapped yesterday and yes, Mrs Middleton had ensured there were enough sausages for the barbie.
"It's going to be strange on Monday," she said.
"But then it's been strange for a while with all the kids leaving."
She said the years of photos and albums collected would be offered to the museum in Waipawa, along with a special "time capsule" of letters created by children for the 50th anniversary of the school and marked "to be opened in 2019."
The school's resources would go to other schools in the region.
The land for the school had effectively been gifted to the Ministry of Education for a peppercorn rental by the owners of Oueroa Station. Mrs Middleton was unsure what would become of it now, but had been assured that a stand of native trees on the site would always remain.