Mitch Zeisler - Founder, Chief Visionary Officer, Soccer Specialist, Coach

Mitch founded Knucklebones in 2004, after realizing his true passion for bringing athletic opportunities and inspiring play to all ages.  He holds a bachelor's degree in Sociology from Hofstra University, a master's degree in Elementary Education from the University of Northern Colorado, and spent over 5 years of his life backpacking around the world.

Mitch currently resides in Brighton, has completed four NYC marathons and scoots everywhere.  In his spare time, Mitch is the Founder and Executive Director of The UrbanSoph Initiative.

Erin Fleischer - Chief Operating Officer, Basketball Specialist, Coach

Erin joined the Knucklebones team in the summer of 2008, after meeting Mitch while watching a Red Sox game.  Sharing Mitch’s love for athletics, children, and play, she realized what a special company Knucklebones was growing into.  Before Knucklebones, Erin attended and graduated from Rhodes College, where she was a member of the Women's Basketball team.

Erin currently resides in Somerville, Coach’s Basketball for 8th grade girls (in the winter) and LOVES to travel.

Find out more about our coaches...

They [Knucklebones] both made it a point to talk with the teacher and I loved how they introduced themselves to the kids. They also gave great tips to teachers.”
    - Carol Jacobs, Director, The Children’s

      Center at Milton Academy

Thank you for employing enthusiastic energetic staff to entertain our kids.”
    - Gina Kun, Director
      Meritor Academy

“The performance of the Knucklebones staff representative was of enthusiasm, excitement, and energy.  The children seem to respond well and were completely engaged in the activities that were presented.”
    - Christine Clark, Director,

   BWH Backup Child Care Center

Corey Appel - Coach, Gymnastic Specialist

Corey joined Knucklebones in the spring of 2010.  He spent 10 years as a child care teacher, loving every minute of it!

He grew up in Revere, MA and received his undergraduate degree from the University of Tampa.  He is now in the process of completing his master’s degree in early childhood education at Cambridge College.  When not coaching he enjoys working out, traveling, and playing sports.

Alyson Humphreys - Coach, Basketball and Softball Specialist

Everything in Alyson’s life has always centered around being active. As a youngster she was an avid cyclist and a triathlete (playing soccer, basketball, and softball in high school and college). As an adult she became more heavily involved in adult recreation leagues and has been known to play on more than one team for each sport she plays, each week!

Being a Coach for Knucklebones allows “me to get others involved in what I love to do, in the most positive and exciting environment possible!”.  She’s currently attending Boston University for her Masters in Physical Education and Coaching and after graduating next year plans to obtain a Certificate of Advanced Graduate Studies in Health Education. She intends to become a personal trainer but, in the meantime she’s a part-time Physical Education teacher for the high school where she coaches the girls basketball team.  You can often find Alyson taking part in fundraising events that involve physical activity, specifically in the battle against cancer.

Jessica Duff - Coach, Basketball and Volleyball Specialist

Jess is currently a Graduate Assistant at Tufts University where she is pursuing a Master's in Educational Studies, while also serving as the assistant women's basketball coach. Jess grew up playing all kinds of sports, but chose to focus on basketball and volleyball, earning varsity letters at Wellesley College where she attended undergraduate university. Jess currently resides in Somerville and loves bringing her love of sports and athletics to people of all ages. 

Karen Manikowski - Coach, Yoga/Creative Movement/Dance Specialist

Homegrown in America’s heartland, Karen comes to Knucklebones with spunk, experience and a love of all things play.

Karen received her BA from the University of Minnesota and has worked in China and Senegal teaching and playing with kids old and young. When not playing you can find Karen training for her next marathon and studying for her masters in International Public Health at BU.

Josh Manheim - Coach, Hockey & Lacrosse Specialist

Josh was born and raised in New Hampshire where at an early age became enthusiastic and involved in athletics. He has been playing hockey since age 4 and in high school, was a Division One All State Selection in both hockey and lacrosse.  More recently, Josh played lacrosse for Bentley College. After graduating from The University of New Hampshire in 2009, Josh went on to receive his Masters of Education in Athletic Administration from Endicott College. In his free time, Josh loves playing hockey, watching sports (especially the Boston Bruins), snowboarding, and is an avid graphic novel enthusiast. Josh currently resides in Medford with his fiancé and 2 cats. Josh joined Knucklebones in the summer of 2011 and is thrilled to be part of such an exciting organization!

Jessie “DC” Duarte-Cherrie - Coach, Basketball Specialist

Jessie was born and raised in Roxbury, MA and always had a love for sports especially her favorite - basketball. She has been playing basketball from elementary school up to high school where she received much recognition and awards. She was MVP, team captain, participated in the 3-point competition and the all star game. Jessie recently graduated from Johnson & Wales University, earning her Bachelors degree in Sports and Entertainment Management. She plans on attending UMass Boston in the winter of 2012 to receive her Master's degree in sports management, and hopes to achieve her dream goal of becoming a woman's basketball coach.

In her spare time she enjoys coaching, playing basketball, listening to music, playing the drums, and hanging out with friends. She is known for her bright smile and is very much a people person. Joining Knucklebones the summer of 2011 was an exciting opportunity for Jessie and she is looking forward to the future with the company.