This is the third in a series of weekly guides to museums
you may not have discovered.

If you’ve ever fantasized about controlling the fate of humankind using a video game, the Marian Koshland Science Museum will fulfill your mad-scientist vision. With exhibits that allow you to spread or cure infectious diseases with a button or prevent climate change via touch screen, Koshland provides the kind of interactives that encourage personal engagement. The space is small, but the exhibits offer tremendous depth. You could easily spend a couple of hours here and not realize how much time has passed. The museum, closed while a new global warming exhibit is installed, will reopen to the public Thursday.

You’re a lifesaver: In an activity in the Infectious Disease exhibit, you select a tuberculosis patient on a screen and determine the number of doses of antibiotic treatments to give him. Slide the screen along a bar to see how the number of doses affects the patient’s well-being and the amount of bacteria left in his system. The power to cure him is in your hands: You decide if you want to keep giving antibiotics.

Catch the fever: In another Infectious Disease installation, you’re given the authority to determine the fate of the world’s children. (It’s really the little things . . . .) As health commissioner, you choose how many children to vaccinate against the measles and influenza, then watch the illness spread. For anyone born in post-vaccination America, it is incredible to witness how these illnesses could swallow populations whole in a matter of months.

On the bright side: Lights at Night allows visitors to compare images of the world — illuminated to represent how much electricity was used in any given location — from 1993, 1997 and 2003. The map can be used to tell history through electricity. Watch the lights go out as the Soviet Union collapses, see them dim in Ukraine in 1997 because of the economic depression, watch cities become more energy-efficient by 2003. Zoom in on your home town to see how much energy you consumed. You also can access this exhibit at home from Koshland’s Web site.

Don’t drink the water: A section on the impact of public-health measures on mortality rates will remind you of just how rare access to basic sanitation is. More than 1 billion people worldwide still have no access to clean water, and 2.6 billion lack basic sanitation.

Like a heat wave: The Earth Lab, which will be open for the first time Thursday, focuses on climate change. Visitors can explore ways to combat global warming while being consistent with your values — so if you, say, couldn’t care less about animals but strongly support oil independence, you can exercise those beliefs in the lab. Four touch screens will enable multiple visitors to play at once, allowing for side-by-side comparisons and some good competition.

Marian Koshland Science Museum

525 E St. NW. Open 10a.m.-6 p.m.daily except Tuesday; $5 admission, $3 for students, seniors and active military. 202-334-1201.