This time of year is always a big moment in retail — it’s the time you start to see aisles of the store devoted to pens, marble notebooks and three-ring binders.

Now you’ll probably also find hand sanitizer in the aisle. And parents dragging their kids to the store to buy clothes that actually fit them.

This year, Deloitte expects back-to-school spending to reach $32.5 billion for K-12 students, which works out to just over $600 ($612, specifically) per student. But there’s a lot going on that makes this back-to-school season different and less predictable.

A lot of kids went to school remotely last year. So, like a lot of us adults, they could get away with wearing pajama pants or shorts.

“That happens for school too, the, you know, ‘business on top and then party on the bottom,'” said Tracy Hurley in Naperville, Illinois.

Now a growing teenager, her 13-year-old son doesn’t fit into his old pants. So Hurley is going to have to buy him clothes for the school year. 

The same is true for Janelle Domeyer in Omaha, Nebraska, and her 15-year-old twin boys. Their school had hybrid classes last year.

“I expect to buy more clothes because they will be there every single day,” Domeyer said.

One thing she said will help: the expanded child tax credit. People are now getting more money from the federal government if they have children, and they’re getting it upfront. For Domeyer, it’s an additional $500 a month. 

“I think it will affect how I spend just in terms of I won’t have any anxiety over any increased cost or buying extra clothes that they will need,” she said.

A lot of families also received stimulus checks over the past year and have saved up money.

“So generally, when you see savings rates go up and we get into a season, usually consumers will spend a little bit more,” said Rod Sides, a vice chairman at Deloitte.

So there are lots of reasons to think people will spend more money on back-to-school supplies this year.

But remember that problem we’ve been telling you about with supply chains?

“Retailers continue to struggle to get product in for varied reasons,” said Sonia Lapinsky, managing director at AlixPartners. “There’s still supply issues in different countries, because countries are grappling with COVID.”

It’s not clear if people will be able to buy everything they want for the school year and, with prices going up, whether they’ll be willing to pay what it costs.