After nearly two decades of writing, recording and touring together, jazz trio Medeski Martin and Wood keeps their material new and interesting as they bring it to the Westcott Theater, 524 Westcott St., on Thursday, Nov. 18, for an 8 p.m. gig. They also, perhaps more amazingly, still like each other.

"When we started we were always hanging together," says bassist Chris Wood in a phone interview. "We were living in New York City, going out together, cooking together, rehearsing, touring, we went to Hawaii in the winter and lived in a shack. We spent lots of time together. It's more complicated the older you get with kids and all, but we still get along great."

In fact, one of the benefits of their latest project, the Radiolarian series (Indirecto), was that it forced the group to reconnect, rekindle their creativity and expand artistically. The project required keyboardist, organist and pianist John Medeski, drummer- percussionist Billy Martin and bassist Wood to write an album's worth of material within four days, tour playing only that material and then record it at the conclusion of the tour.

Then they did it three more times, creating Radiolarians I, II and III released in September 2008, April 2009 and August 2009, respectively. They also released a comprehensive box set in December 2009 including all three of the Radiolarians albums, bonus tracks, remixes, a 70-minute live album, a double vinyl LP and a DVD feature film directed by Martin titled Fly in a Bottle.

"We set up that structure so we would write a lot of new music and we did," says Wood. "Three full records of all original material was a big growth spurt for us. We explored, tried new things out and pulled off the box set."

Although Wood admits releasing so much material in such a short period might not have been the best commercial decision, artistically, it was worth it. "But that's why we have our own label," Wood notes, "so we can do that stuff until we go broke."

Wood was available for a phone interview between tours with MMW and The Wood Brothers, a band he and brother Oliver Wood formed around 2005. Although the side projects the three engage in keep them apart for substantial amounts of time, that also allows each member to bring new ideas back to the group.

"I get a little whiplash sometimes," says Wood. "But it also keeps me on my toes musically. There's a lot of variety, so it keeps things fresh. It's a lot of work, but it's great and I'm happy."

MMW's performances tend to sound fresh naturally, given their style of music: improvisational and wildly innovative jazz. The trio allows grooves to grow and solos to jump among the musicians, each of whom use unrestricted techniques and never shy from experimenting with an idea. On this tour, the group will perform songs from the Radiolarians series, their children's album Let's Go Everywhere (Little Monster Records) and older material.

Songs from MMW's children's album are especially appropriate paired with those from the Radiolarians series, as the latter may not have been possible without the former. "When we did the children's record-not knowing what to do and then only having four or five days to record-the whole record taught us a lot," explains Wood. "We didn't agonize. We wrote quickly, recorded and after that it gave us the confidence to really trust our instincts and ultimately enabled Radiolarians to happen."

The Radiolarians series and children's album, featuring their own children, are two examples of how MMW keeps their music evolving, but the trio finds other ways to challenge themselves as well. Last August, the third Camp MMW was held in the Catskill Mountains at Full Moon Resort for five days.

"We didn't really know how it would work until we got there, but the first year was so successful," says Wood. "I don't usually teach, I'm just a touring musician, so the experience is really learning-intensive for me too. It forces us to think, reflect and interact."

The camp is designed for musicians age 16 and older to broaden their approach to music and learn from the members of MMW themselves. Campers attend workshops and seminars, learning new listening skills and improvisational techniques with the help of special guests and group collaborations. The youth not only gain incredible experience learning and playing with some of the best musicians in the genre, but also help the members of MMW to grow as well.

"Teaching is like looking in a mirror," says Wood. "When you're face to face with someone, you learn a lot about yourself. Where you want to take the music. You have to think about how to communicate that face to face."

Although Wood believes some of their best gigs are at the camp thanks to "that whole interaction," if the Westcott show is anything like Medeski Martin and Wood's performance there last November, audience members won't leave disappointed.

Tickets for the all-ages show run $25 to $30 and are available at www.thewestcott theater.com and at Sound Garden, 310 W. Jefferson St.

-JESSICA NOVAK