The Phillips Collection’s “Jasper Johns: Variations on a Theme,” ushers in a summer of shows celebrating 20th-century American modernism. (Jasper Johns)

A threefer of summer shows is celebrating that theme, under the umbrella of “Modern American Genius.” All open this month.

The first, “Jasper Johns: Variations on a Theme,”arrives this weekend at the Phillips Collection. The show examines some of the painter and printmaker’s enduring visual fascinations: flags, targets, numbers, his signature cross-hatching and the artist’s studio itself.

On June 10, The National Gallery of Art opens “In the Tower: Barnett Newman.” That show will focus on Newman’s shift in the 1940s from loose, organic forms to a more linear style, as well as examples of his most mature work from the late 1950s and 1960s. The Corcoran Gallery of Art will wrap things up on June 30 with “Richard Diebenkorn: The Ocean Park Series.” The show looks at the painter’s seminal series of abstractions made in his Santa Monica studio between 1967 and 1985.

Admission to the Phillips is free this Saturday and Sunday. Admission to the Corcoran is free every Saturday through Labor Day. And of course, the National Gallery is always free.

Read on for more tips about what art you can look forward to this month:

The Diebenkorn exhibit isn’t the only show at the Corcoran with a coastal theme. For those who can’t get away to the shore this summer, the museum is offering some vicarious sun and surf via “The Deep Element; Photography at the Beach.” It opens June 9, and features work from the late 19th century to today.

The weekend of June 16 looks like a good time to visit Baltimore; that’s opening weekend for two cool museum shows there. At the Walters Art Museum, ordinary folks were invited to “crowd-curate” a show — with assistance from the staff. The resulting exhibition, organized around the theme of “creatures,” is called “Public Property.” And at the Baltimore Museum of Art, work by regional artists Lisa Dillin, Jon Duff, Hasan Elahi, Matthew Janson, John McNeil and Renee Stout will be showcased in “Sondheim Artscape Prize 2012 Finalists.” One lucky artist will win first prize in that annual competition, which this year has been increased from $25,000 to $30,000.

June 16 is also the date for the Pile of Craft festival at Baltimore’s St. John’s Church. The offbeat celebration of indie and alternative craft is free, and features home goods, apparel, jewelry, accessories, ceramics and paper goods by more than 45 artisans .

Finally, a few gallery openings to keep in mind.

June 2: “Urban Decay 3”opens at the Workhouse Arts Center with a celebration of lowbrow and street art, especially the genre known as urban vinyl, in which artists decorate customizable plastic dolls.

June 8: Gallery B opens an exhibition showcasing the work of finalists in the Bethesda Painting Awards competition, which hands out $14,000 to the top winners.

June 14: McLean Project for the Arts opens “Something and Nothing: Activating the Void,”a group show around the themes of space, inclusion and absence.

June 25: In a graduation ceremony of sorts, Hamiltonian Gallery opens “Fellows Converge.” Curated by artist Zoe Charlton, the show features work by each artist who participated in this year’s artistic mentoring program, known as the Hamiltonian Fellowships.