Rappy Halloween is not your average fundraiser.

In lieu of bake sales, GoFundMe’s or charity races, this particular benefit features the rap stylings of Joe Wheeler, who by day coordinates employee volunteer projects at San Francisco’s Dropbox.

In the first iteration of Rappy Halloween, Joe held a whopping 12-hour freestyle rap session at his office. Anyone could make a donation and suggest a topic – any topic — and Joe would riff on the spot (or post a rap on YouTube), all for the benefit of Mission High School.

“Joe Wheeler is one of a kind, and his sense of imagination, community and commitment is awesome,” Mission High School Principal Eric Guthertz said. “The Rappy Halloween has become something of a fundraising legend for which our Mission High Foundation is very grateful.”

For the third annual event, Joe along with friend and fellow artist Simone Stolzoff decided to open the floor and invite local artists to join them in a larger bash. Anyone can come to the Center SF this Wednesday at 8 pm and pay a suggested $15 donation to hear from Joe and Simone along with musicians like Frak, Polaroid and Kaila Love. Joe’s also invited the high school students to perform.

“I want to make it a celebration of art in general and invite more people in to be a part of the performing,” Joe said. “I want to get more people tuned into Mission and the work that staff there are doing, as well as the partnership with Dropbox.”

Joe came up with the idea for the fundraiser soon after Dropbox partnered with Mission High through the Circle the Schools program, which matches local companies with public schools.

Joe considers it his job to help coworkers spend time on the causes they feel passionate about, so when he considered what his pet project might be, he decided to combine something he’s loved since high school — freestyle rapping — with a cause he felt was important — helping students get a chance to tour college campuses. He collects the donations for Mission High School’s On the Road to College program, which sends underrepresented students on multiple college tours. Last year Rappy Halloween raised more than $2,500 for the program.

“I think it’s such an important trip for the group of students that goes on it,” Joe said “It opens their perspective to the academic opportunities that are out there.”

Those who can’t make the event but would like to donate can send money to Joe’s Paypal or Venmo (joewheeler541@gmail.com or @joewheeler) or can check out the Mission High Foundation.

“When everything aligns I think its similar to an athlete being in the zone,” Joe said of his love for freestyle rap. “You can make really, really cool moments happen.” Channeling that passion in a way that makes a difference is “a really good way to bring communities together and rally around this particular cause.”