Scatter bands (referred to as scramble bands by some) are an offshoot of “traditional” (corps- or show-style) college marching bands. Like traditional marching and pep bands, they perform at intercollegiate sporting events (most typically during the halftime break at football games, though many also play in the stands at basketball and hockey games). Their similarity to traditional marching bands pretty much ends there, though. A basic run-down of everything you ever wanted to know about scatter bands:

Halftime is game time!
Like any marching band, football halftime is the centerpiece of scatter bands’ performance. (It’s a different kind of centerpiece, though; don’t think of elegant candles or a vase of flowers. Think of that macaroni noodle and cardboard turkey you made for the Thanksgiving table in kindergarten. The one that looked like an alien. *That* kind of centerpiece.) Instead of marching around the football field during their halftime show, scatter bands “scatter,” or run haphazardly, from one formation to the next. They typically perform music while standing in formation rather than while moving around, because it’s hard to blow a horn when one is running haphazardly. The content of their halftime shows also differs significantly from that of traditional marching bands. Instead of playing three or four stylistically-related songs while making abstract formations like rhombi and swirlygigs, scatter bands base their shows around a plot spoken by the band’s announcer. The music and the formations they make go along with the plot of the show. The shows are usually humorous, and generally poke fun at either a) current events, b) the other school, or c) their own school. Sometimes all three in one show. It’s kind of like sketch comedy with music. The humor’s a little geeky, but what else can you expect from band geeks? (For examples of halftime humor, check out the links at the bottom of this writeup, particularly the Rice University one, where you can find archives of past show scripts.)

Scatter bands’ structure is generally much looser than that of traditional marching bands. In order to keep membership and member happiness up, most do not require auditions, nor do they have strict attendance policies. Many will take any and all instrumentalists, including electric guitars, bagpipes, violins, didgeridoos, steel drums, kazoos, etc. Some also take non-instrumentalists for use as dancers and prop people (halftime shows can include anything from large cardboard Saddam Hussein cutouts to explosives and flaming sousaphones, all of which necessitate prop people); these people are referred to as “miscies” (for ‘miscellaneous’) or in one particular band, “Squids” (origin unknown).

Another important characteristic of scatter bands is that they’re normally very student-run; while the administration may keep some sort of watchful eye out (see next section for more on that), students usually do almost everything: write the halftime scripts, arrange music, serve as drum majors and squad/section leaders, run rehearsals, act as liaisons between the band membership and the administration, drum up support/look for new members, organize trips to other cities for away games, design band websites, buy the alcohol, throw the parties, etc.

Trials and tribulations…
Unlike traditional marching bands (often referred to as “the PRIDE of Fill-In-The-Blank University”), student-run scatter bands’ relations with the administration are often tenuous at best. This is dangerous because bands are traditionally expected to represent the school at sporting events, provide support and spirit, etc. The ones that don’t do this adequately don’t get lovin’ from their administration, and the reverse of that is also true; those bands that don’t get adequate lovin’ from their administration tend not to view rallying support for their sports teams as their main priority. They generally take on a “fuck it, let’s do what we want” attitude.

Of course, many bands do get financial and/or moral support from their university’s athletic and music departments. These bands thrive because the affection (read: money) of the university provides an incentive for the band to stay in the university’s good graces, which in turn acts as a check on the band’s humor and/or shenanigans, allowing them to stay in good standing not only with the powers that be, but with other universities. For example, if Columbia University’s administration had cared enough about the band to give them some kind of faculty proofreader (which many scatter bands are admittedly reluctant to bow to – but hey, we’re college students, we think we’re all mature and responsible and stuff), the line “Tuition prices are going down like an altar boy” would have probably been struck from the CUMB’s 2002 halftime show at Fordham University, a Catholic school. The band *and* the university would have been saved a lot of embarrassment and apologizing.

The University of Virginia Pep Band got into similar, though much deeper, trouble by making fun of West Virginia’s hillbilly image at the 2002 Tire Bowl. Arch-rivalries excepted, making fun of other schools in halftime shows doesn’t sit well with anyone, including a) the administration of the other school, b) the administration of the scatter band’s school and (most importantly) c) wealthy alumni. After the Tire Bowl Incident, some rich UVA alums finally decided that they would donate a wad of cash so that the school could have a “real” marching band. Thus the Pep Band will soon be defunct, or at least un-invited from official university events. Bummer for them.

Who ARE these people?
The scatter-band phenomenon is not a widespread one; there are reportedly only 12 college-level scatter-style marching bands in the U.S.A., and none that I am aware of in other countries. These include every Ivy League school except Cornell University (which has a traditional corps-style band), Rice University, Stanford University, UVA, Villanova University, and Williams College. Scattering isn’t exactly an ancient practice, either; all of these bands evolved from traditional to scatter-style sometime in the years since 1950. I haven’t found any one school that claims to have founded the practice. For more information on any of this stuff, here are some links to the websites of (most of) the scatter bands:
The Brown University Band
The Columbia University Marching Band
The Dartmouth College Marching Band
The Harvard University Band
The University of Pennsylvania Oxy-Moronic Fighting Quaker Marching Band
The Princeton University Band
The Rice University Marching Owl Band
The Leland Stanford Junior (pause) University Marching Band
The University of Virginia Pep Band
The Williams College Mucho Macho Moocow Marching Band
The Yale Precision Marching Band

Join one if you have the chance. It's pretty cool. Unless you go to that one school. They're lame.