During her 15 years teaching at Farmington Public Schools, Colleen Stamm would typically start each year with a trip to the store, where she would stock up on everything from pens and pencils to notebooks, folders and pencil sharpeners.

One year, she went even further. Stamm bought 30 buckets at Home Depot, and fashioned them into stools using wood and foam. The reason: She wanted her middle school students to have a place to gather in a close, informal setting for discussions and lessons.

But it came with a price tag.

Stamm, who's now a math and science coordinator for the district, estimated she would often spend more than $500 on classroom supplies.

For years, she used the federal educator expense tax deduction to recoup up to $250 of her expenses.

But with federal lawmakers working to rewrite the tax code, that deduction is now in limbo. A proposal approved Thursday by the House of Representatives scraps the deduction, while the Senate wants to boost it to $500.

Though Stamm is no longer a day-to-day teacher, she says she's disappointed by the prospect of the deduction being eliminated. Teachers feel obligated to provide students with learning materials, she said, and if the government were to eliminate the reimbursement, it sends the wrong message.

"It's just saying to me that my profession is not valued," said Stamm, who serves as the treasurer for her district's chapter of the Michigan Education Association, the state's largest teachers union.

President Donald Trump and Republicans in the House and Senate are pushing to revise and simplify the tax code - eliminating numerous deductions in the process - with the argument that doing so will generate economic growth and ease the tax burden on Americans at all income levels.

U.S. Rep Bill Huizenga, R-Zeeland, said the tax plan passed Thursday by the House simplifies the tax code, eliminates loopholes, and delivers "tax relief for hardworking middle class families and small businesses."

Democrats argue that the GOP tax plan is geared toward corporations and the wealthy and, if signed into law, would result in millions of Americans -- particularly middle- and lower-income families -- paying more in taxes.

Teachers unions across the U.S., including the MEA, have pushed back against the GOP tax plan and the elimination of the educator expense deduction.

Paula Herbart, president of the MEA, called the proposed elimination of the credit a "slap in the face" to teachers, and urged Michigan's congressional delegation to oppose the GOP proposal.

"Every educator I know dips into their own pockets to provide needed classroom supplies that schools and students cannot afford," she said in a statement.

Adopt-A-Classroom, a Minnesota-based nonprofit that collects funds to help teachers cover classroom expenses, estimates that 91 percent of teachers purchase supplies for their classroom, with the average teacher spending $600 annually.

Huizenga spokesman Brian Patrick said the House tax plan will "provide teachers with more money in their pocket than the current $250 deduction" in part because it doubles the standard deduction from $6,000 to $12,000 for individuals and $12,000 to $24,000 for married couples.

"Bottom line, our plan delivers tax relief for educators as well as the families of the students they teach," he said in a statement.

As the tax reform legislation moves forward - Trump says he would like to see it pass by Christmas - the fate of the educator deduction remains unclear.

This week, the Senate revealed an updated tax reform proposal, which, instead of eliminating the deduction, would double it to $500. According to Education Week, Sen. Susan Collins, R-Maine, helped introduce the $250 deduction in 2002, and is seen as one of the Republicans who could block the bill from passing.

Stamm says doubling the size of the deduction is a positive step, because most of her colleagues are "spending that and more."

"That's much more realistic," she said of the amount.

Kristan Small, a teacher at the Lansing School District, said she uses the tax credit for masking tape and folders, as well as groceries such as pickles and pizza dough that she incorporates into math lessons.

"I've got all my receipts filed," she said.