3rd grade🍎👧🏼📚📓

A photo posted by Jamie Lynn Spears (@jamielynnspears) on

Proof that time flies! Jamie Lynn Spears took to Instagram to share a photo of her 8-year-old daughter, Maddie, on her first day of third grade.

In the adorable snap, the uniform-clad elementary student looks more grown up than ever as she poses on the steps of her school. “3rd grade🍎👧🏼📚📓,” Spears, 25, captioned the sweet shot of her not-so-little girl.

On August 7, 2013, the Zoey 101 alum posted a pic of herself and a then 5-year-old (and much smaller) Maddie as she entered kindergarten. When you compare the new photo with the 2013 'gram, which Spears captioned, “#k5 #maddieb,” you can see how much the cute kid has matured since then.

#k5 #maddieb

A photo posted by Jamie Lynn Spears (@jamielynnspears) on

During a June appearance on the Today show, the “Sleepover” singer opened up about the joys of motherhood.

"There's a lot of surprises," she said of the experience. "The biggest thing for me is the sense of purpose I have every day when I get up. No matter what it is, whether it's taking her to school or doing something like this today, there's just a different motivation behind what I'm doing."

However, Spears — who caused a media firestorm in 2007 when she announced that she was pregnant and expecting her first child at 16 years old with ex-fiancé Casey Aldridge — wasn’t always so comfortable in her role as a young mom.

"The biggest difference is that I was a baby and I needed to grow up," she told Today.

Britney’s younger sister tearfully recounted her teen pregnancy as part of her recent TLC documentary, Jamie Lynn Spears: When the Lights Go Out.

"I look back now, and I'm like, 'Oh my gosh,’” Spears said. “I was a child then. I needed to grow up outside the world’s view.”

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