Has social media made teen life more difficult?

Popularity, cliques, acne, social mortification: Adolescence has never been easy. Has the viral world of social media changed this, or merely allowed teens and tweens to experience this passage in a different way?

The CNN Special Report “#Being13: Inside the Secret World of Teens” (8 p.m.) reflects the findings of a two-year study. After gaining permission from students and parents, researchers monitored more than 150,000 posts made on Instagram, Twitter and Facebook over a period of six months by hundreds of eighth-graders. Participants and their parents also completed surveys about social media’s impact on their relationships.

Host Anderson Cooper speaks to participating family members as well as child psychologist Dr. Marion Underwood and sociologist Dr. Robert Faris to sift through the findings — good, bad and ugly.

Portwenn enthusiasts are in luck. And you know who you are. The long-anticipated seventh season of “Doc Martin” arrives on these shores, exclusively on the Acorn Streaming service.

Martin Clunes, who plays the socially awkward and blood-averse physician in a picturesque Cornish seaside village filled with eccentric characters, was recently seen as Arthur Conan Doyle on the “Masterpiece” presentation “Arthur & George.”

Restoration expert Paul Shull hosts “The Weapon Hunter” (7 p.m., Smithsonian). Over the course of a season he will join scholars and weaponry buffs to search for guns, artillery and antiques that have been used throughout the history of warfare. First up, a cross-country trip to locate World War II sniper weapons, including the British Lee-Enfield, the American M1 Garand, the German Mauser K98, and the Soviet SVT-40. Shull and his panel will put these 70-year-old artifacts to the test to determine which was the deadliest sniper rifle of the war.