Two of America’s iconic musical genres are featured in the top two items of this week’s performing arts schedule. In each case, there are significant twists and alternate takes.

The Ossipee Valley Music Festival began about two decades ago as one of several fine bluegrass festivals in Maine. But over the years this annual South Hiram alfresco gathering has gone beyond bluegrass, edging toward a broader concept of American music.

Prefer vintage rock and roll? In Brunswick, Maine State Music Theatre is running its most nostalgic offering of the summer. “Grease” is a Broadway musical with a sound and feel that’s straight out of the 1950s.

Prefer classical? New and old are both present in spades in Brunswick as the Bowdoin International Music Festival enters its final week.

Ossipee Valley Music Festival

In the final summer of the 20th century, the Ossipee Valley Bluegrass Festival was founded on the banks of its namesake river on a fairground in South Hiram, about 45 minutes west of Portland.

Nearly two decades later, the festival remains a pillar of Maine’s summertime performing arts schedule, but it’s been renamed and somewhat re-purposed. I’ve attended most of those years, and plan to go again this weekend.

This year’s Ossipee Valley Music Festival runs July 27-30. The top acts are slated to perform Friday evening, Saturday from noon to late evening and Sunday until mid-afternoon.

Bluegrass remains part of the festival, but there are many variations, and it’s fair to loosely categorize the whole lineup as “old-timey.” Americana is another broad description. Plus there’s a heavy emphasis on female performers and ensembles.

A total of 25 national, regional and local acts have been booked by Ossipee impresario Bill Johnson.

This year’s top billing goes to the Grammy Award-winning Steep Canyon Rangers. These six guys have won wide acclaim as Steve Martin’s band. However, they have been digging themselves a deep, rich home in bluegrass and roots music in their own right for 15-plus years.

The top-billed woman is Nellie McKay, an inimitable, and delightful songstress, actress, comedian and storyteller. Her career has spanned the gamut from Doris Day cover songs to her own wry jazz and folk numbers to musical theater. Sierra Hull, mandolin wiz and singer, is the top-billed woman on Friday’s program.

Among my personal favorite local acts are New England Bluegrass, three guys and two ladies from seacoast New Hampshire, and Lula Wiles, three women from Boston who have strong Maine connections.

Ossipee Valley sports a true alfresco festival atmosphere, including multiple food vendors and retail sales. Bring folding chairs. (A tent is available in case of rain.) Overnight camping is also available. Visit ossipeevalley.com.

‘Grease’

For its penultimate offering of 2017, Maine State Music Theatre has chosen one of the most nostalgic shows ever to appear on Broadway. “Grease,” a tuneful and thoughtful look back at high school in the 1950s, has book and score by Jim Jacobs and Warren Casey plus additional songs by John Farrar.

“Grease” imagines the senior class of fictional Rydell High School in 1959, and the dozen or so significant characters mostly comprise a bunch of lovable misfits who are roughly divided into two factions: the Burger Palace Boys and the Pink Ladies. The primary romantic pairing involves the show-off leader of the Boys sparring with the ingenue, a lovely blonde from a very conservative family who tries to fit in with the rough-and-tumble Ladies, but doesn’t cut it.

The long-lasting appeal of this show is the romance between two very different people who think they know who they are and where they fit, but discover they need to change to become whole.

During the 1970s, “Grease” held the record for longest-ever run on Broadway, and it was later made into a sensationally successful movie. “Grease” remains one of the most frequently produced shows at all levels of American theater.

The score is a pastiche of styles popular in the 1950s, recalled so faithfully that one might assume that “Grease” is a jukebox musical. But it’s 100 percent original with Jacobs, Casey and Farrar.

I loved this production. Neil Starkenberg and Chelsea Williams are perfect as the juvenile-ingenue pairing. Williams is a Maine native who grew up in Windham and is making great headway on a career in professional musical theater.

For the show’s second-tier romance, Kevin Neitzel and Gerianne Perez are equally well matched. Charis Leos, as Rydell’s principal, is hilarious as one of the handful of adult characters.

Maine State Music Theatre presents “Grease” through Aug. 5 at Pickard Theater on the Bowdoin College campus in Brunswick. Call 725-8769 or visit msmt.org.

Bowdoin International Music Festival

They’re counting down to the end of 2017 at the Bowdoin International Music Festival in Brunswick, but a huge sample of the whole spectrum of its many and varied offerings can be experienced over the final eight days.

A pair of concerts remain in the Festival Friday series. Two modern classical composers who highlight the festival’s longstanding commitment to today’s cutting-edge music will be featured this Friday. A percussionist will play flower pots (yes) alongside a cellist in Pulitzer Prize-winning composer Caroline Shaw’s work, “Boris Kerner,” named for a transportation engineer who developed an influential theoretical model for vehicular traffic. It is juxtaposed with Andrew Norman’s “Gran Turismo,” inspired in part by traffic flows of another sort: high-speed race cars in video games. In more traditional fare, a string sextet by Johannes Brahms will conclude the evening.

On August 4 – the final date of the 2017 festival – piano virtuoso Joseph Kalichstein will direct and interpret Beethoven’s magisterial Piano Concerto No. 5. It’s been a specialty of the world-renowned pianist since 1970. Other composers on this program are Johann Sebastian Bach and Arnold Bax.

On July 31 the Monday Showcase series concludes with the Borromeo String Quartet playing works by classical giants Felix Mendelssohn and Robert Schumann plus 20th-century avant-garde composer Gyogy Ligeti.

On August 2 the Festival Wednesday series concludes with a concert that opens with Louise Farrenc’s Piano Quintet. Farrenc was a 19th-century pianist, pedagogue and music theorist at the Paris Conservatory.

This Saturday and Sunday mark the final two concerts of the Gamper Festival of Contemporary Music. Gamper programs aren’t announced in advance, but they normally embrace works by festival faculty composers, their top students and guest artists.

Eight free concerts in the Young Artists series are scheduled between July 28 and August 4, plus there are several remaining free Community Concerts. Many events take place on the Bowdoin College campus in Brunswick. Visit bowdoinfestival.org.

Tunes and dance styles of the 1950s are featured in “Grease,” the current offering at Maine State Music Theatre in Brunswick.