1) “Nature,” 8 p.m., PBS. Every second, we’re told, 3,000 tons of water – enough to fill an Olympic pool — pour down Niagara Falls. The falls themselves (shown here) are fascinating, but this terrific film also has glimpses along the way. We see people nurture a tree that’s been there for 13 centuries and help a snapping turtle whose ancestors go back 90 million years.
2) “Abbott Elementary” season-finale, 9 p.m., ABC. One of TV’s best comedies, “Abbott” is already finishing its 22-episode season. (This summer, a new “Wonder Years” season will take its place.) At least, it ends big, with an overnight field trip to Philadelphia’s Franklin Institute. The Janine/Gregory scenes feel a bit forced, but the rest are a delight, including a panic over outer-space aliens and a tour guide who needs guidance.
3) “Snowfall” series-finale, 10 p.m., FX. This has been a great series, but now it must tumble toward its inevitable conclusion. Franklin was desperate to retrieve the $70 million Teddy stole from him; that hope vanished when his mother killed Teddy. As last week ended, police were arriving.
4) “Changing Planet,” 9-11 p.m., PBS. In a massive Australian expanse, almost twice the size of Vermont, there’s a tiny town, population 160. These are indigenous people, many hired as rangers to manage all that land; they seem to be good at it, using anything from preventative fires to culling herds of wild camels. That’s one of many portraits in this opener, arriving three days before Earth Day.
5) ALSO: Another terrific “Schmigadoon” arrives today on Apple TV, this time with Melissa and Josh trying to brighten the grim 1980s musicals with bursts of romance. And NBC has an all-rerun night for its Chicago stories, peaking with a potent hour: Evidence indicates Sean O’Neal, the police chief’s son, has young women hostage. Hailey Upton (superbly played by Tracy Spiridakos) and Hank Voight rush toward a powerful conclusion.
— Mike Hughes, TV America