It’s a glaring irony that’s also a major force behind class- and race-based discrepancies in academic achievement. In what’s often referred to as the “homework gap,” the unequal access to digital devices and high-speed internet prevents 17 percent of teens from completing their homework assignments, according to the new Pew analysis, which surveyed 743 students ages 13 through 17. Black teens are especially burdened by the homework gap: One in four of them at least sometimes struggle to complete assignments because of a lack of technology at home. And close to half of teenagers in the bottom income bracket have to do their homework on a cellphone occasionally or often.

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From a history-class assignment on the political debate over immigration to required participation in an online discussion board for AP Environmental Science, access to a functioning computer and high-speed internet is all but a prerequisite for success in high school. This is becoming especially true as schools gravitate toward software where students file assignments and papers virtually, as well as schools that equip each student with a laptop or tablet ; one 2017 survey found that half of U.S. teachers have one device for each of their students, up 10 percentage points from the year prior. Close to two in three teachers use technology in their classroom daily, according to a separate 2017 survey .

The homework gap can have major consequences, with some studies suggesting that teens who lack access to a computer at home are less likely to graduate from high school than their more technologically equipped peers. The “challenge to complete homework in safe, predictable, and productive environments can have lifelong impacts on their ability to achieve their full potential,” wrote John Branam, who runs an initiative to provide lacking teens with internet access, in an op-ed for The Hechinger Report last year.

Although the big telecom providers offer subsidies to low-income families, these programs are generally underused . And while disadvantaged students can resort to public libraries and other venues that offer free Wi-Fi, such alternatives are still major obstacles to finishing homework every night. “Your aunt has internet access [at home] but she lives a 40-minute bus trip across town,” Branam wrote, illustrating the roadblocks for teens without internet access. “The public library does, but it has a 30-minute computer use limit and, as a young woman, you don’t feel comfortable there late at night. McDonald’s has free Wi-Fi but it’s noisy, you have to buy food and you can’t linger there forever.”

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