The first lady and the young heartthrobs spent Sunday promoting the First Bloom conservation program by helping students make seed balls from compost, clay, native grass seeds and water.
After Mrs. Bush donned gloves to pitch in, the brothers followed suit.
Nick, 16, needed a little help, however. After he rolled a muddy ball, he displayed it to a young girl standing next to him and asked, "Make it bigger?"
"No, smaller," she advised. He did as instructed.
"Did y'all ever think you'd be making seed balls with the Jonas Brothers?" Mrs. Bush asked the kids, who were from the Boys and Girls Club of Greater Dallas and Williams Preparatory School.
"No!" came the quick reply. Followed by giggles.
A ReunionThis isn't the first time the Jonases have spent time with the first lady; they performed at the White House Easter Egg Roll for the past two years.
"They were our stars, as you might imagine," Mrs. Bush told PEOPLE. "The kids were just thrilled when they got there and found out that the Jonas Brothers were singing. We just got to be friends."
Nick Jonas said of performing at the White House, "It's been an honor every time. Definitely a dream come true."
The Jonases have since recorded a PSA for the government's Get Outdoors, It's Yours! campaign.
Dallas NeighborsThe Bushes and Jonases will soon practically be neighbors. The president and first lady plan to live in Dallas after his term ends, and the guys recently bought a house in nearby Westlake.
"We're looking forward to it," Mrs. Bush said of the couple's imminent move. "George and I lived in Dallas when he was elected governor, so it's been 14 years since we've lived here. It is home."
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