Kanye West & Kim Kardashian Prioritizing Time With Kids

Kim Kardashian and Kanye West are no longer together, but they're both making an active effort to spend quality time with their kids ... proving family is the most important priority.

The SKIMS mogul put on her mom hat Tuesday, sharing on social media a back-to-school photo of herself with all 4 of her kids -- North, 11; Saint, 8; Chicago, 6; and Psalm, 5.

Kim offered up a sweet smooch while she snapped a selfie with her kiddos ... some of whom looked more excited for school than others. Little Psalm sported his famous dad's signature scowl posing alongside his older siblings.

The children may be readjusting to the West Coast time zone ... they joined dad Kanye in China for his 'Vultures 2' listening event over the weekend.

As TMZ previously reported ... all 4 West kids joined Ye onstage for his show at the Wuyuan River Sports Stadium in Hainan when he performed "EVERYBODY" -- his take on the Backstreet Boys classic.

While Ye and the kids had a memorable time in China, the rapper made sure to get his brood back to the States in time for the start of school.

In fact, photogs caught Ye and his wife, Bianca Censori, shuttling the little ones through the airport after the sold-out performance.

Check it out ... Kanye, decked out in an all-black sweatsuit and glasses, kept a low profile as he guided Saint and North through an international terminal. Bianca trailed her hubby and step-kids ... wearing one of her infamous nearly nude ensembles.

Chicago and Psalm were also in attendance ... though, they were tended to by a team of nannies and security guards.