It's a little after 6 p.m. at the McDonald's in Robbinsdale, and it's packed. Every table on the east side of the restaurant is filled to capacity.

Milkshakes, soft drinks and the occasional bag of fries are spread out on the tables next to sheets of paper and stacks of loose change. The clientele, predominantly senior citizens, listen in anticipation as an employee named Jason reads off numbers from a table near the center.

"Bingo!" a woman at a corner table yells. She holds her card in the air and walks over to Jason, who checks the numbers before handing her a coupon for a free sandwich.

The crowd clears their boards, steals sips from their drinks and waits for the next round to start.

McDonald's: Not the first place one would think of to host a bingo game. And yet, said Golden Valley resident Lynne Bergman, it's a weekly tradition that's been going on for years.

"A few years ago my husband and I saw a sign at the McDonald's in Golden Valley that said they were hosting Senior Bingo at 9 a.m. on Tuesday mornings," she said. "We thought, 'Hey, we should do this sometime.'"

Eventually, they joined a game -- and loved it.

"Now we go every week. It's just been so much fun for us."

Armando Lema, manager of the Robbinsdale McDonald's, said the games at his restaurant -- on Tuesday evenings at 6 p.m. and Saturday mornings at 9 a.m. -- have been in high demand ever since they started.

Tim Baylor, a former NFL defensive back who now owns several McDonald's restaurants in the Twin Cities area, started the bingo games at his Golden Valley restaurants on Wednesday evenings several years ago.

Once he took ownership of the Robbinsdale store, Lema said, he brought bingo with him. "It's become this huge tradition here now," he said.

Over the years, the games have become less exclusive. Originally just for seniors, they're now open to anyone.

Bingo cards are free to collect, and everyone who wins a round gets a free sandwich.

Paul Johnson said he and his 8-year-old son Rusty came across the games last month.

"We had some time to kill, so we walked in here on a Tuesday and saw all these people," he said. "We thought, 'What's going on here?' Then we decided to play. Now we come every week.

"It's a nice little game I can play with this guy," he said, pointing his thumb at Rusty. "It's good to help him concentrate and learn numbers. He's at a good age for it, I think."

Bergman said she's met a lot of friends at bingo, referring to the group as a "family."

"We've gotten to know each other really well," she said. "If someone is gone, we notice. People send cards when others are ill, we have gatherings outside of this -- it's really our own little community.

"Being retired, it's really nice to have these kind of friendships, especially as we get older."

Eric Larson is a Twin Cities freelance writer.