Back-to-school means back to shopping. But this year more consumers are going "old school."

According to a recent survey, consumers are returning to malls and other brick-and-mortar stores for backpacks, crayons and more. Meanwhile, shoppers for school items will spend twice as much in-store as online, according to this year's annual "Back-To-School" survey by the consulting firm, Deloitte.

Average spending on apparel, school supplies, electronic gadgets and more is expected to hit $510 per household this year. And $292 of that, or 57 percent, Deloitte found, will be spent in-store.

That's more than double the $115 parents expect to spend on online shopping for back-to-school, or 23 percent of spending. Shoppers are undecided about where they will spend the remaining 20 percent: Either online or in-store.

"People have really been focused on the convenience and making it easy," Deloitte's Rod Sides told CNBC's On The Money in an interview, especially when they search for school clothes. Sides is a Deloitte vice chairman and leads the company's retail, wholesale and distribution division.

"Because the kids grow so often you want to make sure you have the right size, (and) it's just sometimes easier to go to the store," Sides said. "If something doesn't fit, you don't have to worry about the (online) returns process. That's what drives back-to-school specifically versus maybe some other times of the year."

Back-to-school season runs between July and September, during which American households are projected to spend $27.6 billion. That makes it the second busiest shopping season, behind only the holidays.

Which types of retailers did Deloitte's survey find are benefiting from the back-to-school traffic?

"That would be your Walmart's and Target's of the world," said Sides, with big box retailers doing "quite well" overall.

He added that "off-price retail" stores like TJ Maxx and Marshalls, "and dollar stores have done extremely well in the last couple years and have really come into prominence in this season."

Deloitte's survey showed another shift in back-to-school shopping habits. Use of laptops dropped from 57 percent last year, to 49 percent this year. That nearly mirrored the rise of smartphone use for shopping, from 49 percent in 2017, up to 53 percent this year.

"They're moving from that stationary big unit to the mobile unit," Sides told CNBC, "but what we're finding is that they're using that mobile unit all throughout the shopping journey. So it's a little bit easier to use the phone and phones are a bit bigger than they were a few years ago."

As back-to-school shopping season winds down, are the last minute bargains to be found online or in-store?

"There's going to be offers in both places, but there's a real need to get the items in your hands faster," the analyst said. "So I think in-store is going to be a big part of where we see a lot of the deals."

That's because, he points out, December is fast approaching.

"Especially as retailers look to clear out some of the old inventory before they get into the traditional busy season of the holidays," Sides added.

"On the Money" airs on CNBC on Saturdays at 5:30 a.m. ET, or check listings for air times in local markets.