They were having a blast. During the annual Royal International Air Tattoo in Gloucestershire, England, on July 14, Prince George, Princess Charlotte and Prince Louis were invited to climb inside a Royal Air Force C-17 for the ultimate VIP tour. As their parents, Prince William and Princess Kate, looked on, the future king and his siblings raised and lowered the plane’s loading ramp, checked out the controls, and explored the nooks and crannies of the enormous aircraft. “The look of wonder on their faces,” a royals insider tells Life & Style, “was priceless.”

And that’s just one of many exciting adventures the Prince and Princess of Wales’ children have experienced in recent weeks. In May, they were front and center at grandfather King Charles III’s historic coronation, then got to watch Katy Perry and Lionel Richie belt out their hits at a concert capping off the historic event. In June, Louis, 5, stole the show with his antics on the balcony of Buckingham Palace during Trooping the Colour. And in July, two days after the air show, Charlotte, 8, made her Wimbledon debut alongside big brother George a week before he celebrated his 10th birthday. Kate and William, both 41, “are doing all they can to ensure the children have a wonderful time now that school’s out,” says the insider. “It’s really shaping up to be George, Charlotte and Louis’ best summer ever.”

The Wimbledon Tennis Championship men’s final on July 16 marked a big day for the eldest Wales kids. Though Louis was “very upset” he didn’t get to join them, Kate had shared, Charlotte and George — “who’d been eagerly watching” the earlier matches, Mom revealed — didn’t let that stop them from cheering from their front-row seats in the Royal Box during a nail-biting five-set match between Carlos Alcaraz and Novak Djokovic. Charlotte also spent time chatting with tennis legend Chris Evert, who was seated behind her and later called the young princess “absolutely delightful!”

The kids are also having fun away from the spotlight. “They’ve been spending lots of time at Anmer Hall,” their country home on the king’s Sandringham estate, says the insider. “Kate regularly plays rugby in the back garden with the children — she plays all sports with them,” Nigel Gillingham, president of the Rugby Football Union, revealed in June, noting that Charlotte, like her mother, is “very competitive.”

Before the kids return to school on September 6, the family will enjoy some time away together. “They love visiting Tresco Island in the Isles of Scilly,” on the coast of Cornwall, says the insider, “or they’ll rent a villa in Mustique again.” A trip to the king’s Balmoral estate in Scotland to visit with extended family is also in the cards. “Kate is pretty strict during the school year — with homework, after-school activities and early bedtimes. But she sees the summer as a time when they can let go of their rules a little bit and just enjoy themselves.”