All staff members at Many Rivers Montessori are interviewed, hired, and trained in compliance with guidelines set by the state of Minnesota. Each of our staff members has a background in education and/or child care. We facilitate relationships between staff and children that are nurturing, responsive, supportive, and respectful, encouraging creativity and independence in the student. Every one of our classrooms has a lead teacher, or Guide, certified by the Association Montessori International (AMI-USA). We currently employ seven AMI-certified guides and have four classroom assistants with AMI Montessori assistant training. Our maximum teacher-to-student ratio goals are as follows: 1:15 in Elementary, 1:10 in Primary, and 1:4 in Toddler.

Jessica Mohn-Johnsen  |  Guide, The MRM Middle School

Jessica comes to the MRM Middle School as a progressive educator with deep experience with middle schoolers. For most of her teaching career, Jessica taught middle schoolers and elementary students in Waldorf schools in Portland, OR and in La Crosse, WI. She holds a Master of Education degree from the University of Wisconsin-La Crosse, a Bachelor of Applied Science from the University of Minnesota Duluth, and will attend AMI Montessori Adolescent training in Ohio this summer.

As a Waldorf middle school teacher, Jessica is well-versed in establishing traditions around curriculum and community culture. She has guided culminating research projects and presentations, led wilderness field trips, staged theatrical works, and helped students run small enterprises. “Through my years as a teacher and a learner, I have discovered that an education that accounts for the diversity of learners is one that inspires students to work hard and continue to learn,” explains Jessica. “I see the MRM Middle School as a place where students will drive their education and seek purpose in their work in a developmentally responsive way.”

A Duluth native, Jessica returned to the Twin Ports in 2014. While Jessica enjoys working with her hands, she can also often be found adventuring outdoors with her family on foot, bike, or boat. “The forests and the Lake are truly home to me,”  she says, adding: “I'd like to one day circumnavigate Lake Superior by kayak.”

Andrea Christopherson  |  Guide, st. louis river Elementary environment


Andrea is an AMI-certified Montessori elementary teacher with ten years of full-time experience, most recently as lead elementary guide at a local Montessori school. She also holds a BA in Elementary Education with a minor in Social Studies from the University of Minnesota Duluth. A native of Detroit Lakes, MN, Andrea moved to Duluth after high school and has stayed put ever since. She loves that Duluth is a city known for its beautiful outdoor features and unique local attractions, and “not for its malls.” When not planning lessons or thinking about school, Andrea is usually busy cooking or creating messy projects with her two children, setting up family exercise challenges, walking in the woods with her husband, digging in her gardens, reorganizing a closet, or kicking back with a good book. Andrea is excited to help shape a school culture focused on the love of learning and the embrace of a Montessori community, and is eager to help build a supportive and inspiring work environment.

Courtney Bartz  |  Guide, st. louis river Elementary environment


Courtney holds a BA in Environmental Science and Elementary Education from the College of St Scholastica, and is an AMI-certified Montessori elementary teacher. She started as an assistant teacher in a Montessori classroom in Duluth in 2008, and assumed the role of lead lower elementary teacher in 2010. She has also served with Americorps and worked as a camp counselor, nanny, volleyball coach, reading tutor, and as a teaching assistant in the public schools. Courtney loves Duluth for its people, its sense of community, and its physical beauty. In her limited spare time, she loves to run, ski, bike, or go camping, or to snuggle indoors with her family doing some sewing, knitting, or reading. She enjoys working alongside like-minded colleagues to develop a school atmosphere of community involvement, trust, growth and open communication, and loves being able to say: “I teach at Many Rivers Montessori!”

Rebecca Tollefson  |  Guide, Chester Creek Primary environment


A native of Bemidji, Becca graduated in 2014 from the Montessori Center of Minnesota with her AMI Primary diploma. Prior to attending AMI training, Becca taught for seven years at Child Garden Montessori School in Minneapolis, both at the Primary and Infant levels. When she is not teaching or spending time outside, Becca might be found singing with her daughter, sewing, “fairy gardening,” playing board games, or curled up with a good book. She enjoys taking her daughter out for walks through the woods or by the beach. Becca loves to guide the children along their natural path of development, offering them “keys to the world in a concrete form.”  

Sheena rogers  |  Guide, Tischer Creek Primary Environment

Sheena graduated in 2015 with her AMI Primary Diploma from the Montessori Center of Minnesota. She also holds a Master of Arts in Education from St. Catherine's University and a Bachelor of Science degree in Human Development and Family Studies from Colorado State University. A native of Roseville, MN, Sheena has been part of the faculty since 2015, when she joined MRM as Assistant in the Chester Primary Environment. Sheena is excited to "build an environment of beauty that excites children and leads to life-long learning," and proud to be "part of MRM bringing the Montessori philosophy to the Twin Ports." When not at MRM, Sheena can often be found walking or bicycling on the Lakewalk with her husband, traveling to national parks, sewing, and curling up with a good book.

maddie keeler  |  Guide, Lester River Primary Environment

Madelaine Olson (1).jpg

Maddie received her AMI Primary Diploma from the Montessori Center of Minnesota in 2015, and holds a BA in Psychology from the University of Minnesota Morris. Maddie is also the daughter of a Montessori guide, and a Montessori alumna from Primary through eighth grade. Maddie has served as lead staff with the YMCA childcare program in Andover MN, as a teacher's aide at Oak Hill Montessori in Shoreview MN, and has tutored elementary children through a program with UM Morris. Maddie loves Duluth for its combination of urban and natural spaces. "It is so rewarding to come to work every day and be surrounded by such hard-working, like-minded people," says Maddie. "Everyone is so committed to the children, and you can see the joy and pride that they take in their work. I am so happy to be a small piece of that group and cannot wait to continue spreading Montessori through the Twin Ports." When not in the classroom, you can typically find Maddie playing with her French Bulldog, testing out a new recipe in the kitchen, or reading a book.

madeline Jeffery  |  Guide, Amity Creek Toddler Community

Madeline completed her AMI Assistants to Infancy training at The Montessori Institute Denver in the summer of 2016. She holds a B.S. in Art Therapy from the University of Wisconsin-Superior, and has attended the AMI Assistants Course at the Montessori Training Center of Minnesota. She has also served with True North Americorps at Bay View Elementary School in Duluth. Madeline loves Duluth's weather, and enjoys all the festivals in Duluth and the surrounding region in the fall. She has been a part of MRM since its inception, serving first as Chester Primary Assistant and then as Amity Toddler Assistant. She enjoys the friendly, positive, and joyful families at the school, and is grateful to be able to watch her students change and grow. When not caring for MRM's youngest children, Madeline can be found pursuing her loves of travel, camping, and reading.

Kristi VanTassel  |  Movement Guide, One-on-One Support Teacher, Before- & After-School Coordinator


In her new role, Kristi provides one-on-one student support and movement classes to Toddler and Primary students, and coordinates our before- and aftercare programs. Kristi holds an AMI Assistants to Infancy Diploma from The Montessori Institute Denver, and in 2014 launched Duluth’s first Montessori Toddler Community at MRM. She holds Master of Education as well as Bachelor of Applied Science degrees from the University of Minnesota Duluth, and has served as Director of Children’s Ministry at the Duluth Vineyard church, where she worked closely with children and their families. Prior to this, she worked nearly four years at a local hospital, specializing in children’s mental health. Kristi comes from a Montessori family and applies the Montessori philosophy in her own life’s work, household, and parenting journey. She and her husband have four children, love the Minnesota outdoors, and have been known to pack up even the tiniest of their babes and head into the wilderness with their canoes. Kristi is concurrently pursuing her AMI Elementary Diploma at the Montessori Center of Minnesota.

Matt Wahl  |  Spanish

Matt joins the MRM team in 2016 but is no stranger to the community, having been a Montessori parent for the last six years. His background in Spanish, teaching, music and theatre provides Matt with a spectacular skillset to bring into the Many Rivers community. In addition to being a professional musician, Matt holds a Bachelor of Arts in Theatre with a minor in Spanish from the University of Minnesota Twin Cities. He worked in the Eau Claire Area School District for six years as a K–12 substitute teacher with a number of long term placements. Matt is excited to be joining "such a vibrant, hard-working, caring, passionate group of people; their love of children and of the Montessori method comes through in everything they do." When not teaching at MRM or spending time with his wife and two MRM kids, Matt is a performing songwriter. He is also an avid curler who dreams of competing nationally.

From left, top row: Ivy Smith, Trey Carlson. Middle row: Jessica Randall Greeley, Jessi Anderson, Heather Honer. Bottom row: Mari Hardel, Laura Donovan, Emily Davidson.

From left, top row: Ivy Smith, Trey Carlson. Middle row: Jessica Randall Greeley, Jessi Anderson, Heather Honer. Bottom row: Mari Hardel, Laura Donovan, Emily Davidson.

assistant teachers

Heather Honer | Elementary

Heather assists Andrea and Courtney in the Elementary Environment. She has been a Montessori assistant at both MRM and the Montessori School of Duluth, and has held positions in educational, caregiving and business fields. She holds an Associate’s degree from Lake Superior College, and has completed the AMI Assistants Course at the Montessori Center of Minnesota. She has served at Mother Teresa’s orphanages and Gandhi’s School of Learning in India, as well as an orphanage in Uganda. She is also a children's choir director, hangs out with teenage international students, and would some day like to help meet the growing needs in St. Louis County by opening a crisis home for young children.

LAURA DONOVAN  | Chester Creek Primary

Laura assists Becca in the Chester Creek Primary Environment. She has been a teaching assistant for 18 years, including five years as a Montessori assistant. Laura holds a bachelor’s degree in Psychology and has completed the AMI Assistants Course at the MontessoriCenter of Minnesota. The mother of two grown daughters, Laura loves the “big-small town atmosphere” in Duluth and during the summer can be found sailing on the Big Lake.

Trey Carlson | Tischer Creek Primary

Trey assists Sheena in the Tischer Creek Primary Environment. A psychology major at UW-Superior, he has held various youth program positions at the Duluth YMCA, and has also worked at a local Montessori school. Trey has been on the MRM faculty since its inception, and has attended the AMI Assistants' Course at the Montessori Center of Minnesota.

EMILY DAVIDSON | Lester River Primary

Emily assists Maddie in the Lester River Primary Environment. Emily holds a BA in History with a focus in First Nation Studies from UWS, and has been program director of the Boys & Girls Club on the Vermilion side of the Bois Forte Reservation. She has also completed the AMI Assistants Course at the Montessori Center of Minnesota. A growing interest in Montessori pedagogy led her to her current position at MRM. Emily is a student of the Ojibwe language, and, when not working with children or reading, is often found lavishing her attention on her pets and plants at home.

Jessica Randall Greeley | Toddler

Jess assists Madeline in the Amity Creek Toddler Community. She comes to MRM with a wealth of teaching experience in early childhood, elementary education, and special education settings. She holds a B.A. in Elementary Education with a minor in Spanish from Wartburg College, and is licensed in Minnesota for K–6 Elementary Education. Jess and her family moved to Duluth from the Twin Cities in 2015. When not caring for our youngest children, Jess enjoys hiking, camping, and being outdoors with her family; and reading, embroidery, rock collecting and playing with her cat.

Julie Allen

Julie cares for the children in our before- and aftercare program. Julie earned her BA in International Studies and Environmental Science from DePaul University, and her professional work entails organic farming and environmental education.

Sara Curwin

Ivy Smith

Ivy joins MRM this year after graduating from The College of St. Scholastica with a B.A. in Psychology in May 2016. She has held positions in childcare and aquatics, and is excited to remain in Duluth, with its wealth of outdoor activities and opportunities. Ivy is new to the Montessori philosophy, but eager to learn from MRM's committed Montessori faculty. Ivy is a former collegiate ice hockey player who continues to play, but who also loves to be outdoors, to teach swimming, and to practice yoga. Her long-term goal is to pursue further studies in Psychology, and to either work at a pediatric mental health center, or become a licensed counselor.

Kaelyn Williams


mark niedermier | Head of School


Mark joined MRM in 2015 with 30 years of experience in education as a Head of School and teacher in progressive independent schools. He brings to MRM a proven track record in running and growing strong schools. Prior to MRM, Mark served as Head of School at the Logan School for Creative Learning in Denver, CO; Pacific Northern Academy in Anchorage, AK; and Friends School of Minnesota in St Paul. A native of Ohio, Mark received his B.A. in Liberal Arts from St. John’s College in Annapolis, MD, and a M.A. in Psychology from the New School for Social Research in New York City. He has been a Math, Science, and Ancient Greek teacher, a seasoned chaperone of overnight trips, and is a trained conflict mediator for children and adults. A passionate long-distance road biker and Nordic skier, Mark enjoys Duluth for its balance of urban amenities and outdoor access. Mark’s vision is for MRM to become recognized locally and nationally as a leader in Montessori education, “an amazing school that is an important piece of the fabric of our thriving northern city of Duluth.” He describes the MRM community as “warm, enthusiastic, committed, visionary, and collaborative,” and adds: “There is a real excitement at MRM about bringing a new school to life, and this energy shines.” Mark and his wife reside in Duluth and have two children.

Brenda Ciardelli | Admissions director

Brenda holds a B.A. in Criminal Justice, worked for several years with adjudicated youth, and began working with children in childcare settings while still a teenager. She has also been involved in the opening of and management of several restaurants, and has always thrived in “a setting where you are creating something from the ground up.” A key part of MRM’s Launch Board, Brenda feels blessed to have helped to found a school that will have a lasting impact on the children of the Twin Ports. “I’m in awe of what a group of people with a common goal can do if they set their hearts and minds to it,” says Brenda, who has two children at MRM.


L: Kelsey Tessier. R: Melissa Anderson.    

L: Kelsey Tessier. R: Melissa Anderson.



Melissa assists Head of School Mark Niedermier, and also enjoys helping out around the school wherever her sunny, warm presence is needed. Melissa studied Education at UW-Superior but has since worked in the business field, most recently as Director of Operations and Events for a local non-profit organization. Melissa has been on the MRM staff since its inception. “To be involved in such a positive and important venture in our community is very rewarding, and so much fun!”

Kelsey is the friendly and efficient office assistant you will often meet at the front desk. She holds a Bachelor's degree in Psychology with a minor in Human Development and Family Studies, and has also worked in after-school positions with Lester Park Elementary School and Jumpstart. She is also a coach with the Arrowhead Youth Soccer Association. Kelsey values the opportunities to connect daily with the children outside of their classroom environments. She is a lifelong Duluthian who thrives on being able to "drive 30 minutes in any direction and find a lake to spend the day at."

board of trustees

Matt Cartier, parent, president of Cartier Agency, active community member in local arts and area nonprofits

Brenda Ciardelli, Admissions Director, parent, criminal justice background, opened several restaurants

Jeff Engbrecht, parent, founder/CEO of Clearwater Composites

Mike Karstens, J.D., community member, former Montessori parent, attorney

John Kliewer (Chair), J.D., parent, pastor, former corporate attorney and biotech executive

Jennifer Lien, D.M.A., parent, musician, former business journalist

Elena Metcalf, parent, M.D. specialized in child development and mental health

Rita Rosenberger, parent, over 15 years’ involvement in Duluth non-profits

Carin Skoog, parent, former public policy coordinator/consultant

Barbara Welinski, M.S., former Montessori parent, business owner, former school counselor and teacher