Students and teachers had been working on the surprise for the past few weeks, but they had challenges since Mabry is always around, working from 6:30 a.m. to 5:30 p.m.
Lori Gilreath, a reading teacher at the school, said Mabry feels to her like he’s part of her family, after working together for the past decade.
"He's just very caring. He's just so much more than just a staff member. He doesn't know how special he is," Gilreath told CNN.
Gilreath’s classroom was the command center as they wrapped up creating the celebration.
Once Mabry left for the day, work got started on decorating the school, creating a birthday throne and lining the walls of the school with photos, all with the theme "80 years loved, 80 years blessed," CNN reported.
The students listed 80 reasons why they love him, reasons like taking time to hug them, or give them a pat on the back when they need it..
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Mabry, who was the first person at the school last Wednesday, got the surprise when he turned on the lights, then got to work preparing the building for classes. When Gilreath got to the school, Mabry was hard at work vacuuming, according to CNN.
That all changed when the kids started arriving and the day turned from education to celebration.
And you’d think at the age of 80 he’d be looking at retiring, but nope, Mabry is in it for as long as he can be.
"As long as I'm able to work, I think I'll work," he told CNN.
As for his kids, "They're like my children. I'm like the old lady in the shoe," Mabry told The Washington Post.