What do you call the headings along the top of a newspaper that reference later page articles?

Solution 1:

These are called ears.

From a glossary of newspaper terms:

Ears- Space at the top of the front page on each side of the newspaper's name where ads, weather news, index to pages or announcement of special features appears.

From Merriam Webster:

6: a space in the upper corner of the front page of a periodical (as a newspaper) usually containing advertising for the periodical itself or a weather forecast

Solution 2:

The OP is asking about the series of illustration-and-teaser-headline combinations that appear near the top of the front page of a newspaper (or on the cover of a print magazine). At the magazines where I've worked, we called those design elements "skyboxes"—a term that most people in the United States associate with luxury (or executive) suites at football and baseball stadiums, but that has a very different meaning in publishing. From Chuck Klosterman, All I Know Is What I Read in the Papers: An Essay from Sex, Drugs, and Cocoa Puffs (2003):

People also like graphics, especially pie graphs. Photographs are also profoundly important, even if it's just a photograph of someone standing in front of the T.G.I. Friday's they happen to manage. And don't forget about sky boxes! People desperately need “sky boxes,” which are eye-catching charts that tell them about news stories hidden inside the same paper everyone assumes they don't want to read. ...

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Here's how the newspaper process operates: Reporters write stories. These stories are read by midlevel editors who tend to make minor content changes. The stories are then pushed to the "copy desk," where copy editors check for grammar mishaps and factual errors (copy editors also write the head;lines). Eventually the stories get to the "design desk," where page designer decides how to place this information on the tangible [a[er page—they decide how to incorporate the news alongside the photographs, graphics, sky boxes, and everything else that really doesn't matter. Their goal is to make the page look pretty; they are akin to architects. Quite simply, they are trying to create a newspaper that can be appreciated by the illiterate.

Likewise, from Debora Wenger & Deborah Potter, Advancing the Story: Journalism in a Multimedia World (2014):

Skyboxes, skylines. Teasers that run above the flag on Page One. If they're boxed (with art), they're called “skyboxes” or “boxcars”; if they use only a line of type, they're called “skylines.”

And from Gaylon Murray, Effective Editing: A Practical Guide for Students and Professionals (2009) [combined snippets]:

STUDY PREVIEW: Items that appear at the top of the front page—whether referred to as hoods, promos, skyboxes or teasers—usually are the responsibility of copy editors. Those boxes give readers an idea of what's inside and and perhaps increase news rack sales.

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On front pages there is space for the flag and room for other regular front-page features, such as indexes. Many newspapers run ears or skyboxes in the flag area. Some newspapers still perform layout with dummy pages on paper, but most layout work is done with templates on computers.

As these citations indicate there are many other terms for the design elements in question, including teasers, boxcars, skylines, hoods, promos, and ears. But skyboxes is the term we used.