(CBS) — Monica and Kate are new pen pals who met for the first time in person on Tuesday. Monica Joria is 100 years old. Kate is 5, and is in kindergarten at St. Cajetan Elementary School in the Morgan Park neighborhood.

Monica and Kate were just one of 17 pairings of old and young pen pals at the Smith Village retirement community.

“We have very active residents here and we thought it would be a good experience for both our residents and the kids,” said Smith Village CEO Kevin McGee.

McGee’s six-year old son, Finn, was among the students who made pen pals with a Smith Village resident. Finn greeted his new friend, 86-year old educator Phil Carlin, who talked with the youngster about the topic of the letter the boy sent to him: leprechauns.

The seniors and the kindergartners also talked about everything, from what their favorite colors were to ways they eat healthy.

The children came prepared with questions they had written down, even if they had trouble reading a couple of the words. But, that was okay. Sometimes one of their new, older friends had trouble in the hearing department.

St. Cajetan’s kindergarten teacher Lisa O’Leary said what started as a service learning project grew into something more.

“We thought what are some good ways to give back instead of always giving donations of money? Our love, our caring, our sweetness, and our kindness are all free,” she said.

O’Leary envisioned organizing future get-togethers, possibly with the seniors visiting the school, or — when the weather gets a bit nicer — having a picnic in Kennedy Park which is across street from Smith Village, on 113th and Western Avenue.

Eileen McAlpine, 84, giggled and smiled and enjoyed her time with 6-year old Annie.

“My grandchildren have gotten old on me so it’s nice to have a younger one around and to write little notes to,” McAlpine said.

Shelly Genis, volunteer coordinator at Smith Village, said, “Sometimes you don’t realize how much you have in common until you start chatting a bit.”

And, from the kids and senior citizens say the darnedest things file: after talking about what he liked to eat after he gets home from school, young Brendan volunteered that he lost a tooth on Monday. His 88-year-old new friend Mary Joan Schuch promptly asked him if he put it under the pillow, which Brendan said he did.

“And the Tooth Fairy gave me, like two coins”, the boy said.

On the senior side, 100-year old Monica Joria, when asked by her new five year old friend, Kate, whether she had a best friend, answered honestly, that, “no, I’ve lived longer than most of my friends.”