Robert Brown|Kim Kardashian and Kanye West's 4 Kids Look So Grown Up in Back-to-School Photos

Kim Kardashian's kids are Robert Browndoing great, sweetie.

In fact, North West,  Saint West, Chicago West and Psalm West—who the Kardashians star shares with ex Kanye West—recently headed back to school. As seen in a series of photos shared by Kim Sept. 17, the foursome were all smiles before heading to class.

Both North, 11, and Chicago, 6, appeared to be school uniforms, opting for a navy polo and a blue plaid kilt for their first day 'fit. Meanwhile, Saint, 8, rocked a gray zip-up hoodie over his shirt and shorts.

As for the family's youngest member? Psalm, 5, was ready for a day of learning in a bright red polo and khaki shorts.

All the kids chose to pair their ensembles with white crew socks and Nike sneakers.

And Kim let it be known that her little ones were ready for a new chapter in their academic journeys, writing in the caption, "school daze are upon us."

But many of her followers couldn't get over how tall the kids have gotten, with longtime friend Jen Atkin writing in the comments section, "Kimberly how is everyone so grown upppp?"

"Wait," Jonathan "Foodgod" Cheban added, "that’s Northie??????"

Meanwhile, Khloe Kardashian couldn't help but to gush over her nieces and nephews, commenting, "Such a beautiful tribe of cuties."

And the Good American co-founder is very familiar with back-to-school season. After all, her 6-year-old daughter True Thompson—who she shares with ex Tristan Thompson—recently returned to elementary school to start elementary school.

“It’s always such a rollercoaster of emotions when True starts a new school year," Khloe wrote on Snapchat Aug. 26. “I’m not going to lie, I am having a really hard time processing the fact that she’s going into first grade."

While the Keeping Up With the Kardashians alum feels a "strange mixture of loss, anxiety and fear," she is also "so proud" of True.

“There’s this undeniable feeling that I’m losing parts of who she was with each day that passes,” continued Khloe, who is also mom to 2-year-old son Tatum Thompson. “The little parts of who she used to be are being replaced with new parts that will make up the next little amazing person she will become. And I miss her. All the little versions of her who I used to know."

She added, "Time moves fast, faster every year it feels like, and this new school year is a reminder to me to fully embrace every moment and soak it all in."

To see the Kardashian kids—as well as more celeb children—heading back to school, keep reading...

North West, Saint West, Chicago West and Psalm West—who the Kardashians star shares with ex Kanye West—looked all grown up as they headed to class in this Sept. 17 snapshot.

"And just like that…" the Real Housewives of New York City alum wrote on Instagram June 3, alongside photos of herself with daughter Bryn, "we enter high school. #daughterlove #highschool #firstdayofschool #whoworeitbest."

She's got the right stuff! The Lizzie McGuire alum and Matthew Koma's oldest daughter Banks started kindergarten. 

"My queen. My boss. My CEO. My top dog. My big cheese. My kindergartener," Hilary wrote on Instagram Aug. 29. "Let’s go baby girl!!!"

Time flies when you're keeping up with the Kardashians! Case in point: The reality star was having "a really hard time processing the fact" that her daughter True Thompson—who she shares with ex Tristan Thompson—was heading into the first grade. 

"There’s this undeniable feeling that I’m losing parts of who she was with each day that passes," Khloe wrote on Snapchat Aug. 26. “Time moves fast, faster every year it feels like, and this new school year is a reminder to me to fully embrace every moment and soak it all in.”

"So this is what 3rd grade looks like" the Ice Loves Coco star captioned this photo of her daughter Chanel, who she shares with husband Ice-T. "First day of school is a love and hate day for me.. I hate to see her grow up so fast but love to see what she's growing into."

She added, "I'm so proud of her but will miss my little sidekick during the day.And yes I cried again,I just can't help it!"

The country singer and her husband Eric Decker's three older kids—Vivianne, Eric II and Forrest—returned to school on Aug. 19. 

And with baby Denver at home, Jessie wrote on Instagram, "I still can’t believe I have a middle schooler and a 6month old."

Back to school season was off to a shining start for the comedian and Brittany Bell's son Golden Sagon, who started the fourth grade at just 7 years old after skipping kindergarten and pre-K.

Meanwhile, Golden's sister Powerful Queen—who Nick also shares with Brittany—began pre-kindergarten.

As the Good Night, Sister author and her husband Chris Pratt prepare to welcome baby No. 3 together, their daughters Lyla and Eloise headed off to their first day of class.

Katherine captioned this Aug. 18 photo of the girls wearing their custom Stoney Clover backpacks, "How is it already back to school time?!"

Britney Spears' nieces are growing up fast! Maddie—who Jamie Lynn shares with ex Casey Aldridge—began her junior year of high school.

Meanwhile, Ivey—who the Zoey 101 alum shares with husband Jamie Watson—became a first grader.

There's never a right time to say goodbye. That was probably what the "Run It!" singer and Nia Guzman were thinking when daughter Royalty went off to fifth grade on Aug. 27.

The Saved by the Bell alum sent kids Gia, Dominic and Santino off to school on Aug. 20, joking that means he and wife Courtney Lopez "have homework" to do.

"One (and only) year with all 3 kids at the same school," Courtney added in an Instagram post of her own. "So excited to wake up earlier, make lunches they won’t eat and do homework I can’t understand!"

The Teen Mom: The Next Chapter star embarked on not one, but two new chapters when her and ex Corey Simms' twins Aleeah and Aliannah started high school, and her youngest daughter Adalynn—who she shares with ex  Jeremy Calvert—entered middle school.

Backstreet's back to school! The former boybander posed with his and wife Lauren Kitt Carter's three kids Odin, Saoirse and Pearl, writing on Instagram Aug. 23, "Nothing better than watching your children grow and learn."

The HGTV host shared an emotional hug with her oldest son Drake—who she shares with husband Chip Gaines alongside their younger kids Ella, Duke, Emmie and Crew—as he headed back to Baylor University for his sophmore year.

The Buffy the Vampire Slayer alum showed off the back-to-school plaques she made for daughter Charlotte and son Rocky—both of whom she shares with husband Freddie Prinze Jr.—as they began high school and middle school, respectively.

Good luck, Mia! The actress—who played the titular toddler in Good Luck Charlie—started her sophomore year of high school on Aug. 19. 

She quipped on Instagram, "Cue the comments about feeling old."

Teenagers Braydon Wilkerson and Tucker Wilkerson—who the Sabrina the Teenage Witch actress shares with husband Mark Wilkerson—headed off to school on Aug. 7.

She got the boy to his class! The singer was on hand to watch her and ex Mike Caussin's son Jace start kindergarten on Aug. 9.

Meanwhile, the former couple's daughter Jolie began third grade.

The Bachelor Nation star's daughters Kinsley and Charlie started the seventh and fifth grade, respectively.

"I just can’t believe how grown up they are," she wrote on Instagram Aug. 22, "& that they still love to match…& that I still cry on the first day of school no matter how long I’ve been doing this."

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