MINNEAPOLIS (WCCO) – Eighty-year-old Walter Erickson is a retired teacher who’s been a substitute in a north metro school district since 1991.

“Honestly, I’ve never seen a sub so old, you would think he would be retired,” said Kelsy Breiter, a Champlin Park High School senior.

Almost every day of the school year, Erickson is at Champlin Park High School.

On Wednesday, his students there gave back to him in a way he never would have expected.

“He’s just impacted so many of our lives in amazing ways,” said Katie Blodgett, a senior at Champlin Park. “He’s the kind of substitute teacher where he connects with us more on a personal level and he obviously loves what he does and that makes it more encouraging for us to learn.”

Erickson is saving up to pay for his wife to get cataract surgery and some much needed dental work.

“When we found out the surgery may not be covered, we just wanted to help out,” Breiter said.

She, Blodgett and another friend started a GoFundMe page. Donations, mostly small amounts from students, came pouring in.

“When I told my wife about this last Friday, she said, ‘Who are these girls? What kind of parents do they have that they could be so caring and compassionate?'” Erickson said.

The initial goal was $500.

On Wednesday afternoon, the girls told Erickson the latest numbers.

“Our total is $13,905 that the community and the people at the school have raised for you,” they said.

It seems the students of Champlin Park left a permanent impression on their substitute teacher.

Erickson said he was “just overwhelmed” by the students’ generosity.

“I know my wife will appreciate it very much,” he said. “Thanks a lot, really a lot.”

As for Erickson’s substitute teaching career, he says that he won’t be stopping any time soon.