Katie Holmes and Suri's new life hasn't all been cupcakes, gymnastics classes and trips to the zoo.

Recently Holmes -- who filed for divorce from Suri's dad, Tom Cruise, June 28 -- confessed that her six-year-old is still adjusting to a much more modest lifestyle.

"She said the divorce has been hard on Suri and she's acting out," a Holmes pal told Us Weekly. Still, the Kennedys star, 33, is determined to remain firm and not give in to the elementary schooler's every wishes. "Katie says no to some things, but gives a little leeway. She knows Tom is going to spoil her." (Case in point? The briefly reunited father-daughter pair's $6,000 helicopter ride to the Hamptons over the summer.)

In her first postdivorce interview, Holmes opened up to Women's Wear Daily September 5 about how she's choosing to handle personal challenges post-split -- and how that approach has impacted her parenting philosophy.

Explaining that she's no longer "afraid to fail," Holmes said she's been trying to impart the same attitude to her daughter via arts and crafts projects, which don't always turn out as planned.

"At least you tried," the Holmes & Yang designer said of their creative endeavors (which included gussying up an old shoe rack with spray paint). "I think, 'Oh, I'm a great mom' and then it doesn't pan out the way I think it's going to . . . But the intention's there."

Earlier this month, Suri started school at NYC's elite Avenues, where she'll have to swap her designer heels (so long, $600 Jimmy Choos!) for Lands' End uniforms per the strict dress code.

Holmes, for her part, is thrilled about the opportunity to encourage Suri to wear more casual looks.

Says an insider, "She wants [her] to fit in and be more of a normal kid."

This article originally appeared on Usmagazine.com: Katie Holmes' Divorce From Tom Cruise Has Been "Hard On Suri"