Going broke sending the kids back to school? Average cost of school supplies tops $100

If the words "school supplies" call to mind a few pencils, a notebook, maybe a Trapper Keeper, get ready for the new math: The average K-12 parent will spend $100 per student on school supplies this year, up 12 percent from last year.

And that might be getting off easy. If parents like Kimberly Brown of Salinas, California, bought everything on her child's list, the tab could be as much as $400.

Read: How to save on back-to-school shopping

"It seems like it gets more and more and more expensive," Brown told NBC's Janet Shamlian. "It seems like they're asking for way too much stuff."

School supply lists that schools give to parents for fall may include high-tech items like graphing calculators and flash drives; but they also expect parents to shell out for things like staplers, hand sanitizer, paper plates, even ice cube trays.

Teachers say these lists are just suggestions, and they're not required of anyone.

"There's nothing said to anyone who doesn't bring it," teacher Terese Boronda said. 

Often, in fact, teachers are the ones who end up spending their hard-earned money on school supplies for their classes.

At Tampa's "Twice As Nice" consignment shop, parents can buy new or gently used school supplies at a lower cost. 

Two former teachers opened the store after years of spending hundreds of dollars of their own money on supplies. 

"I think people take for granted that it just magically appears in their classroom, but it doesn't," explains Twice as Nice owner Adrianne Wilson. 

Related: Shop these sites for cheaper textbooks

And school supplies are just part of the back-to-school tab. Add in clothing, shoes and electronics, and the average cost of sending a child to back to class this year is $669.