After a long week of classes, the weekend finally arrives. You are bored, stressed out and ready to go have some fun. But you are also under 21, and it seems that your options for nightlife are somewhat limited in Boston. So where do you go? Some of the most popular spots in the city actually offer nights where everyone is welcome. Check out a few of these clubs and you will not be disappointed.

The Roxy, 279 Tremont St.

(www.roxyboston.com)

On Friday nights, nearby Roxy hosts its 18+ "Sexy Fridays." If you plan ahead and check the Web site for an Internet flier, you will cut the cover charge from $20 to $15. Hip-hop tracks and upbeat remixes of pop songs provide a fun atmosphere for hours on the dance floor. The dress code does not permit anything too casual, however, so leave the jeans, sneakers, work boots, baggy clothes and athletic wear at home.

Freshman marketing communications major Lyndsay Mills, 19, said The Roxy, like many other nightclubs, can be hit or miss. "The atmosphere isn't bad early in the night, but it gets wicked crowded as it gets later, and there are a lot of sketchy older guys," she said. "I wouldn't recommend going there with a group of only girls, but rather with some guy friends to 'rescue' you from the weirdos."

Venu, 100 Warrenton St.

(www.venuboston.com)

Located behind Emerson next to the New England School of Law, this dance club charges a cheap $10 cover that is worth your money. Proper dress is required here as well, so no jeans and sneakers.

Hilary Lawson, 19, a sophomore writing, literature and publishing major, visited the club with friends last Thursday for Salsa Night. "It was amazing," Lawson said. "We were twirled and dipped and it wasn't the usual bump-and-grind." Aside from the spicy salsa music on Thursdays, Citysearch, a popular on-line city guide, credits Venu with having "some of the city's hottest DJs."

Avalon, 15 Lansdowne St.

MBTA Green Line to Kenmore

(www.avalonboston.com)

This popular nightclub is listed in all the best city travel guides, such as Fodor's and Frommer's. Its prime location (right across the street from Fenway Park) certainly helps attract a crowd, and a large one at that: it has a maximum capacity of 2,000 people. A popular dancing spot later in the evenings, Avalon is also a concert venue for many alternative bands. A variety of acts, from Black Label Society (Oct. 25) to The All American Rejects (Nov. 11), have performances lined up. On "Fling Thursdays," the club attracts a big college crowd with a cover of $15 and all ladies are in for free before 11 p.m. You can also get your name on the guest list, via its Web site, for a reduced cover charge.

Hopeful clubgoer Chris Morse, 20, of Athol, Mass., said he stopped by the club with friends on a Thursday for a night of dancing. Upon arrival, however, he was informed that he would not be allowed in. "The bouncer told me, 'No shorts. Only on Gay Night,'" Morse said. Sunday is Avalon's 19+ Gay Night with a cover charge of $10. According to Avalon's Web site, Gay Nights do not have any specific dress codes, and energized house music and drag shows provide the entertainment.

Paradise Rock Club, 967 Commonwealth Ave.

MBTA Green Line to Pleasant St.

(www.thedise.com)

For almost 25 years, Paradise has served the Boston community as one of the most popular rock clubs in the city. It is a smaller venue, with a capacity of around 600 people, but big name acts such as U2, Phish, Rage Against the Machine, Our Lady Peace and Everclear have all graced the stage there, according to its Web site. These days, up-and-coming rock bands like Stellastarr*, Nada Surf and The Dandy Warhols play almost nightly, with ticket prices ranging from $10 to about $25 depending on the act. Most shows are 18+, but make sure you check the Web site or call ahead for details.

If all rock all the time is not your thing, then maybe the neighboring Paradise Lounge, at 969 Commonwealth Ave., is better suited to your taste. Its Web site lists several different theme nights, such as Classic Wednesdays, Mash-Up Tuesdays and Reggae Thursdays.

The Classic Wednesday event occurs the last Wednesday of each month at 9 p.m. and features favorites like 80s pop-rock for a cheap $7 cover. Mash-Ups occur every Tuesday night at 9 p.m. for the same $7 cover, and they feature a DJ spinning hip-hop tracks mixed with just about everything. The Lounge offers free admission to its reggae-fueled nights on Thursdays, which are co-hosted by Emerson's own WERS. The downside, however, is that at 8 p.m. Reggae Thursday goes 21+, so the Lounge is a better spot for early-evening entertainment.

Ryles, 212 Hampshire St., Cambridge

MBTA Red Line to Central

(www.rylesjazz.com)

If you're a jazz fan who could use a serious break from the usual crowded dance clubs and loud rock shows, head over to Ryles in Inman Square. A favorite among locals, the main stage features a number of jazz acts at affordable ticket prices. All shows listed from now through December have tickets on sale that range from around $7 to $15. Or stop by on a Sunday night for weekly Salsa Sundays. A great deal at just $10 per person, Salsa Sundays include salsa lessons beginning at 6 p.m., followed by a buffet-style dinner and then dancing until 11 p.m.

The Middle East, 472 Massachusetts Ave., Cambridge

MBTA Red Line to Central

(www.mideastclub.com)

An avid concertgoer and rock fan, Emerson freshman marketing communications major Ren Walker, 18, said the downstairs of the Middle East is now her favorite venue. "I've been there pretty much every weekend for some show," Walker said. "I have yet to go to a show where everyone isn't having an incredible time rockin' out to the music."

A casual spot with no posted dress code, the Middle East features local, regional and international rock bands such as Architecture in Helsinki. Walker said The Middle East has a relaxed atmosphere, with "a lot of music buffs with great concert war stories. There is a general, overall good feeling and music appreciation." The cover charge depends on the event, but is usually about $10. Some nights, like Open Mike, are free-but you might have to buy some of their chocolate baklava. For tickets, you can either go to www.ticketmaster.com, which adds a surcharge, or the Middle East's box office, open daily until 7 p.m.

Maybe being under 21 does not have to limit your options as much as you had originally thought. And remember, this list only contains a few of the many hot spots for those of us who cannot hit all the bars in the city … yet.