In August, foot traffic fell 3.3% year over year for Target, with the week beginning August 25 (which included the long Labor Day weekend) dropping 4.6%, marking its worst weekly decline in seven weeks, according to data from Placer.ai.

At Target rival Costco, foot traffic was up 5.2% YoY for August, while Walmart was slightly down 0.6%.

On Labor Day, both the American Federation of Teachers (AFT) and the Chicago Teachers Union (CFT) announced they were joining the boycott against Target over it rolling back some diversity, equity, and inclusion (DEI) efforts earlier this year. The boycott, which was spearheaded by black clergy, began in March.

“We rarely engage in this type of action, but we’re doing so here because Target betrayed promises to communities of color throughout the United States,” AFT President Randi Weingarten said in a statement.

On January 23, President Trump vowed to “abolish all discriminatory diversity, equity, and inclusion nonsense,” and Target announced the next day it was ending some DEI initiatives, which Weingarten didn’t think was a coincidence.

“Target rolled back promises to help the people who have been loyal customers, because of a president who is trying to roll back history and ignore the struggle for freedom and justice,” Weingarten said. “Those customers, who have helped Target’s bottom line, now feel set aside, ignored, and dismissed.”

The Chicago Teachers Union added in a statement that it “stands in solidarity with the boycott of Target, recognizing the rollback of its DEI initiatives as part of a broader ideological attack on equity.”

The country’s second-largest teachers union behind the National Education Association, AFT represents about 1.8 million teachers and other workers; the CFT represents about 30,000.

Target did not respond to a request for comment about the foot traffic decline and teacher boycott.

Class struggle: More than 9 in 10 teachers spend their own money on classroom supplies, according to the National Education Association. For the current school year, teachers will spend an average of $895 out of pocket for school supplies, up from $600 in 2015, according to a national survey by AdoptAClassroom.org.

Back-to-school is Target’s “second-biggest season of the year,” behind the holidays, Rick Gomez, EVP and chief commercial officer at Target, said in a June earnings call. In a June report about Target possibly staging a “comeback” during the then-upcoming back-to-school season, Placer.ai said that August historically has been the retailer’s second-biggest month—after December—for store visits.

In a “Teacher Appreciation” section on its website, Target highlights incentives for teachers to buy supplies, including half-price subscriptions ($49) for annual membership to its Target Circle 360 loyalty program, exclusive discounts, and a wishlist tool to build “your dream classroom.”

The retailer also has a “Gift Ideas for Teachers” section with more than 500 items.

“Thanks, Teach!” Target’s website enthuses. “Show a little love to the ones who have taught you the most.”

This report was originally published by Retail Brew.