There is a lot of great jazz coming up in the D.C. area throughout the next week, much of which is FREE, an important word here at DCist. Of course, the big news for jazz aficionados is the annual Big Band Jam, which began on April 20 and runs through April 29. We already told you about the service bands playing at Blues Alley, but there are many other shows to check out. Here are some highlights:

>> The Sylvan Theater, on the grounds of the Washington Monument, will host free daily concerts tonight through Sunday [Update: Saturday's events at Sylvan have been canceled]. Tonight's concert will feature jazz bands from several local colleges while local high school ensembles will be featured on Thursday and Friday. Local community and semi-professional groups perform on Saturday. The Sylvan’s program culminates on Sunday with must see showcase of international talent. The International Jazz Jam features everything from traditional vocalists to more avant-garde work. Highlights from this show include SOLID!, a group redefining the possibilities of the jazz organ trio, Amina Figarova, a talented and prolific pianist/composer hailing from the Netherlands, and the Dainius Pulauskas Group, a genre blending Lithuanian ensemble. The concerts Wednesday-Saturday run 11 a.m. to 6 p.m. while Sunday’s program is from 11 a.m. to 7 p.m. The full schedule of performances is available here.

>> The famed One O’ Clock Band from the University of North Texas, the number one big band from the top university jazz program in the country, is in town for several performances. These future torch bearers of jazz are performing 8 p.m. and 10 p.m. sets at Blues Alley Wednesday through Saturday. The group will also give a free performance at the Kennedy Center’s Millennium Stage on Saturday at 6 p.m.

>> Jazz chanteuse Dianne Reeves graces the stage at The Lincoln Theatre this Friday at 8 p.m. Though her recorded output has its ups and downs, she always delivers a strong live performance that draws upon her considerable influences and talents. Generally recognized as one of the finest jazz vocalists of her generation, Reeves is sure to shine in this historic room. Visit the venue’s web site for ticket information.

>> Local vocalists Felicia Carter, Janine Carter, Sharon Clark, Bonnie Harris and Lavenia Nesmith are featured this Sunday in Sistas Can Sing!: A Tribute to Female Legends in Jazz and Blues, a concert at the St. Thomas More Catholic Church. Saxophonist Paul Carr, pianist Chris Grasso, bassist Wes Biles, and drummer Lenny Robinson will accompany the singers. The show begins at 3 p.m. Contact the venue for ticket information.

>> Much of the city has been peppered with flyers and posters in anticipation of the 21st annual Calvin Jones Big Band Jazz Festival, taking place next Monday at 8 p.m. The concert, hosted by UDC, features the school's top ensembles, as well as those from Howard University and the University of Maryland. Many of the area’s jazz musicians have spent time in one of these three jazz programs. Tickets are $20 with discounts available for students and seniors.

>> For those interested in seeing a great local jazz orchestra in an intimate setting, check out the Thad Wilson Jazz Orchestra at U Street’s historic Bohemian Caverns. The 10-piece group, comprised of some of the D.C. area’s best, performs every Monday night from 8 p.m. to 11 p.m., $10 cover. Wilson also performs with his trio at Jojo’s most Thursdays, no cover.