Detroit ? Abdul “Duke” Fakir beamed as a group of elementary school students crooned an old Motown hit to him and other veteran musicians from Motown Records.

Once they reached “I guess you’d say, what can make me feel this way, my girl,” Fakir — the lone surviving original member of the Four Tops — looked up to the old control room in the record label’s former studio and yelled, “Call the Temps — tell ’em they got 10 more years.”

It didn’t matter to Fakir that the kids were singing a smash hit by the Four Tops’ label mates and sometime rivals, the Temptations, during a tour Monday of the Motown Historical Museum. The impromptu serenade of “My Girl” in the old studio helped mark Motown’s 50th anniversary, showcase its staying power and recognize the label’s legacy — a stable of artists who ruled the charts because camaraderie and competition came in equal measure.

“We helped each other, but we also worked very hard to outdo each other,” said Fakir, who was joined in the erstwhile studio by members of the Motown’s house band, the Funk Brothers, and Rare Earth.

Monday marked the day 50 years ago that Berry Gordy Jr. secured an $800 loan to start the company that soon would spin out chart-topping hits by the Temptations, Four Tops, Stevie Wonder, Supremes, Jackson 5, Smokey Robinson and the Miracles and many others.

Alumni on hand for Monday’s celebration included Fakir, members of Smokey Robinson and the Miracles, Martha Reeves and the Vandellas, and numerous composers, arrangers — even one of Motown’s famed “style and deportment” coaches.

They were on hand to reminisce, serve as tour guides and hear proclamations from local, state and national politicians. Monday was declared “Motown Day” in Detroit and Michigan.

Motown songwriter Ivy Hunter was among those gathered for the festivities in the cramped studio, boasting much of its original analog equipment and adorned with pictures of Little Stevie Wonder and the Temptations recording there. Hunter said the West Grand Boulevard complex was as productive as one of Detroit’s auto factories — churning out records from 1959 until 1972, when the company moved to Los Angeles.

“This place was open 24-7,” he said. “It was the assembly line for the Motown sound.”

Hunter also praised Gordy, who didn’t attend but offered a statement that was read by Robin Terry, the museum’s chief executive and Gordy’s grandniece.

“God bless the dreamer, God bless the dream and God bless the results,” Hunter said.

Fakir, who called the former studio “hallowed ground,” said there’s no single reason why Motown achieved all of its success and impact, but there was something uniting everyone in the building.

“Everything was done with passion. Nothing was done generically,” he said. “The engineers even had passion. They made magic.”