• TikTok's "#underconsumptioncore" trend has been displaced by the start of the back-to-school shopping season — and with it "#backtoschoolhauls."
• This latest hashtag trend comes surprisingly swiftly on the heels of a movement centered around resisting overspending.

Just when it seemed more Americans were inspired by the ideas of "underconsumption core" and "conscious consumerism," which aim to put a lid on social media-influenced overspending, the back-to-school shopping season kicked off early — followed by TikTok hashtag #backtoschoolhauls.

As of the beginning of July, more than half, or 55%, of students and families had already started buying supplies for the start of the academic year, according to the National Retail Federation.

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"The back-to-school shopping season has increasingly started earlier each year," largely driven by retail strategies, said Cassandra Happe, an analyst at WalletHub.

Sales events like Target Circle Week and Amazon's Prime Day started even earlier in 2024, "aiming to capture early-bird shoppers and outpace competitors," Happe said.

Back-to-school spending could reach nearly $40 billion

Families with children in elementary through high school plan to spend an average of $874.68 on school supplies, just $15 less than last year's record of $890.07, according to the NRF.

Altogether, this year's back-to-school spending, including for college students, is expected to reach $38.8 billion, the NRF also found. That's the second-highest tally ever, after last year's $41.5 billion marked the most expensive back-to-school season to date.

According to another report, by Intuit Credit Karma, nearly one-third, or 31%, of parents said they can't afford back-to-school shopping this year and 34% expect to take on debt to cover the cost of supplies.

Higher prices are partly to blame: Families are now paying more for key back-to-school essentials such as backpacks ahead of the new school year. CNBC used the producer price index — a closely followed measure of inflation — to track how the costs of making certain items typically purchased for students has changed between 2019 and 2024.

How much more expensive will back to school shopping be in 2024?

On the upside, starting earlier may offer the best opportunities to find the best deals, a separate survey by Deloitte found, at a time when household finances are particularly squeezed.

"However, this approach can also lead to increased spending due to rising costs and the temptation for impulse buys," Happe said. "Parents might find themselves spending more overall, especially on high-ticket items and electronics."

More than 75% of parents said they believe schools ask them to buy too much during back-to-school season, another report by WalletHub found.

Parents influenced to splurge on 'must-have' items

"Back-to-school hauls have started infiltrating TikTok earlier than I've ever seen it," said Casey Lewis, a social media trend expert and founder of trend newsletter After School.

"As soon as the Fourth of July holiday weekend was over, I began seeing them — and not just shopping hauls, but also outfit ideas and calls for advice about the best shoes and backpacks to buy this year," Lewis said.

Despite having to navigate tight budget constraints, 85% of parents said they could be influenced to splurge on a "must-have" item or brand, Deloitte also found.

According to Lewis, low-rise jeans, $110 Adidas Campus sneakers and Jester backpacks from North Face, which retail for $75 or more, are topping this year's wish lists.

"There's a lot of pressure to have the right look," Lewis said. And as trends cycle through faster and faster, "young people have even more pressure to keep up," she added. "It feels like their popularity and perceived coolness rides on the products they have."

How to keep back-to-school spending in check

Consumer savings expert Andrea Woroch advises families to shop for gently used clothing, sporting goods, school supplies and certified-refurbished electronics on resale sites, use a price-tracking browser extension or app and apply coupon codes. There are a growing number of online retailers that offer children's product overstock, open-box and returned goods, often at a significant discount.

Also take advantage of sales tax holidays when you can, she said. Review the 2024 Sales Tax Holiday list to see if and when your state lifts sales taxes for a few days.

Otherwise, shop your own stock, which is what TikTok's #underconsumptioncore is all about. "Rip out pages in a partially used notebook, collect scattered markers and crayons to make a full set and clean up last year's backpack and lunch tote," Woroch said.

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