Teaching Tree’s mission is to promote life-long learning by embodying the principles of quality and value.
Quality is defined as the adherence to science and maintaining high ethical standards in the pedagogical process without losing empathetic focus on the client. Value is defined as the efficient use of resources by placing effective scientific teaching practices to optimize the number of learning opportunities per any given time.
Teaching Tree’s employees get things done by engaging in a multi-dimensional problem-solving process and data analysis which require self-reflective practice, collaboration, creativity and openness. Our staff learns both from success as well as miraculous mistakes which we define as the courage to go beyond our current comfort zone of what we know and do well.
Our approach is valid as long as it leads to effective actions and meaningful growth, if not – we adapt and modify our programs in response to the environmental feedback. Teaching Tree sprouted in the field of applied behavior science and naturally is rooted in functional contextualism which predicts and changes behavior with ‘precision, scope, and depth’.
Our international staff speak 16 languages! English, German, French, Spanish, Italian, Russian, Bulgarian, Armenian, Belarusian, Catalan, Farsi, Mandarin, Cantonese, Bahasa Malaysia, Indonesian, and Tagalog.
- Behavior Therapy
- Occupational Therapy
Ashley Gibbs, PhD Candidate, BCBA, OTR/L
Ashley grew up in Atlanta, Georgia. She graduated from The Medical College of Georgia (now Augusta University) with a Master of Health Science in Occupational Therapy in 2013. After several years of working with children in a multidisciplinary setting and seeing the gains her clients made when they received ABA services, Ashley decided to return to school and graduated from Georgia State University with a Master of Science in Applied Behavior Analysis in 2018. After conducting her first research study as a master’s student, Ashley developed a passion for bridging the gap between research and practice. She is particularly interested in interventions that facilitate generative language and derived relational responding in children with autism and other intellectual and developmental disabilities and has had her work published in multiple behavior analytic journals. Ashley is working on her dissertation as a doctoral candidate in the Educational Psychology program at Georgia State University.
As a BCBA and an OT, Ashley has had experience working with clients from birth to adolescence with a variety of diagnoses and abilities. Ashley believes in treating the whole child and working in collaboration with providers across all disciplines to advance a client’s independence.
Outside of work, Ashley enjoys spending time with her husband and son, reading, and traveling. In the fall, you can find her wearing red and black and cheering for the UGA Bulldogs in NCAA football.
She speaks native English.
Benjamin Brody, MS, BCBA
Ben has worked with children and teenagers with autism from ages one and a half to eighteen. He began this work in 2017 a behavior therapist in Phoenix, Arizona, before completing his Master’s Degree in Psychology with a focus on Applied Behavior Analysis from Capella University in 2020. He is passionate about providing direct therapy to children and teenagers—and designing individualized programs to help them succeed.
Ben enjoys cooking, walking, hiking, biking, chess, and swimming.
He speaks native English and is learning German.
Carla Meikle, MA, BCBA
Carla has almost two decades of experience working with children with special needs and their families. At Carthage College, where she obtained her undergraduate degree in Psychology, she served as Chapter President of Psi Chi and presented research at the American Psychological Association Convention. She obtained her master's degree in Applied Behavior Analysis with an emphasis in Autism and was nominated by her peers to run for President of Four Corners Association for Behavior Analysis. Carla joined Teaching Tree Clinic in 2018 and has been serving as our Clinical Director since soon thereafter.
Carla plays soccer competitively, hikes with her dogs, and travels as much as possible with her husband and two boys.
Carla speaks native English, fluent Spanish, and a bit of German.
Constanza has lived for over two decades in Germany, hailing originally from Chile.
She began her career as social assistant worker, later becoming a paralegal, and currently serves as an administrative all-rounder.
Her mindset is service-oriented and solution-focused, utilizing creativity, in order to provide outcomes everyone is satisfied with.
Constanza enjoys going on walks with her dog, is interested in everything that is health related, and likes to listen to mystery stories, to cook, and to meditate.
She is fluent in German and English.
David Cole, MS, BCBA
As a researcher, David studied the neuropsychology of fast and slow decision-making in humans and animals. His work has been published in a half dozen journals and has won fifteen grants and monetary awards. A highlight of his academic career was working on a computer game controlled by brainwaves as a visiting researcher at Trinity College Dublin.
As a therapist, a supervisor, a consultant, and a director, David treated toddlers to geriatric patients with diverse psychiatric diagnoses from California to Florida. He developed free graphing software for time-series data that has been adopted by university programs. A highlight of his clinical practice was navigating three adolescents and teenagers from their first words to speaking in sentences in under a year.
In January 2022, David was appointed CEO of Ausblick Therapie GmbH, bringing experience with founding companies, sitting on the boards of nonprofits, and lobbying on Capitol Hill.
David speaks native English, some French, and a bit of German.
Dayra Diaz-Gonzalez, MEd, BCBA
Dayra is a military spouse who is dedicated to helping families. Dayra has been in the field of ABA since 2016, serving young children diagnosed with Autism Spectrum Disorder and their families. She started as a Registered Behavior Technician and maintained this position while she completed her schooling. She attended Arizona State University where she completed a Masters of Education in Curriculum and Instruction with a concentration in Applied Behavior Analysis. She has worked with children and young adults ranging from 2 years of age to 17 years old. She believes in creating individualized programs to help families reach their goals.
Dayra loves to travel. She enjoys trying new foods and spending time with her family.
She speaks native English and native Spanish.
Danielle Trzil, MA, BCBA
Danielle is a Washington State native who found her passion for working with neurodiverse populations while working in a research lab providing parent training. She was inspired by the positive effects of the ImPACT curriculum to families in the Greater Seattle region.
Danielle began working as a behavior technician and assistant behavior analyst before receiving her BCBA credential in 2020. She has experience primarily working with children aged 18 months to 6 years of age with a range of developmental disabilities (including Deaf/hard of hearing, global developmental delays, Down syndrome, and Autism Spectrum Disorder). For the past year and a half, she has been working with a multi-disciplinary team providing services following the Early Start Denver Model in a clinical and preschool setting.
Danielle is passionate about promoting socially significant behaviors and skills in the populations she works with by utilizing naturalistic, developmental/behavioral, and empirically validated practices.
She enjoys spending her free time with her family traveling, going on leisurely hikes, crafting, and being outdoors.
She speaks native English and some American Sign Language.
Diane Fraser, EdD, BCBA-D
Dr. Fraser was France’s first BCBA. She is the Cofounder of Association Française—Les Professionnels de l’Analyse du Comportement (AF-LPA) and the Verified Course Sequence Coordinator for L'Analyse Appliquée du Comportement. She earned her doctorate in education from Columbia University, has held academic posts at Saint John’s University and Long Island University, and has been invited to deliver several keynote addresses at international conferences. She is the author of Comme Font Les Autres Enfants, a book for parents on how to communicate with their children with autism.
She is an American-born native English speaker and self-taught French speaker.
Emily Berman, MS, BCBA
Interim Clinical Director
Before joining Teaching Tree Clinic in 2018, Emily worked for an ABA company in California, climbing her way from behavior technician to clinical director. During this time, she gained experience working with toddlers, children, and young adults in home, school, and community settings.
Emily has experience in Early Start Denver Model, Pivotal Response Training, attending IEPs, providing community training events, and collaborating with large teams of autism service providers. collaborating with large teams of autism service providers. She always aims to provide individualized ABA service focusing on the highest priorities of the families she works with.
When Emily is not building block towers and facilitating social skills opportunities, you can find h hiking, cooking and exploring new cities.
Emily accepted the clinical directorship of our Frankfurt-Mainz-Wiesbaden clinic until we name a permanent replacement, allowing her to maintain a primary focus on the clients she directly serves.
Emily speaks native English and fluent German.
Ivanah Edquiban, MS, BCBA
Ivanah hails from the Philippines, graduating cum laude from the University of the Philippines with a degree in Behavioral Sciences. Sometime later, sitting in front of a computer as a talent acquisition agent, a thought that crossed her mind: She would rather be moving, playing, and working with children.
Six years ago, Ivanah began working a registered behavior technician with children with autism in the Philippines, before completing her master’s degree in applied behavior analysis at Bangor University in the United Kingdom. There, she wrote a thesis on teaching sign language to staff in a nursery using SAFMEDS and Precision Teaching.
Ivanah completed her training to become a BCBA at Teaching Tree Clinic. Since then, she has spent her days working and playing with children and savoring life-changing improvements captured in everyday incremental progress. You could say that this is what reinforces her waking up and walking into work every morning. She cannot imagine doing anything else. She values Teaching Tree Clinic as a place for continued development and learning and where the team cares for the clients and each other.
Ivanah speaks native English and native Tagalog.
Katrin Hechler-Massel, MS, BCBA
Senior Behavior Analyst
Katrin is a native German who will join the Kindsbach clinic in May. She comes with more than a decade of experience in the field, most recently at the Neurobehavior HOME Program and Autism Spectrum Disorder Clinic of the University of Utah.
She speaks native German and fluent English.
Katya Shchurskaya, MA, BCBA
Katya began her career as a language instructor at Minsk State Linguistic University. A few years later she started looking into Applied Behavior Analysis, as her own son was developing with a speech delay, and immediately fell in love with the science. Her keen interest in the area grew into a new profession – she completed the ABA program and obtained her Master’s degree in
Psychology in 2020. For some time, Katya combined her teaching job at the university with work with children with special needs implementing behavior analysis in both settings, but eventually transitioned to the latter. She is truly passionate about her work, as both its process and result give her immense joy and inspiration.
Katya is a constant learner, has a vibrant curiosity for new places, people and experiences. In her
free time, she enjoys travelling, hiking and reading.
She speaks native Russian and Belarusian, fluent English, and some Italian.
Cofounder, Chairperson, & IT Specialist
After studying distributed IT systems, Leif worked for 10 years as an IT consultant in a large German bank. Bored with the high level of abstraction and dissatisfied with the lack of connection to the real world, he quit his job and moved on with the intention of spending time in the forest, away from the modern world—a plan that was thwarted by his wife, who hired him as an employee for their clinic. The clinic flourished and eventually became Ausblick Therapie GmbH, where he served as interim executive director during the start-up and transition period before handing that role over to David Cole, so he could finally devote himself to contemplation and meditation in his cabin in the woods.
He lives with his family in the Palatinate Mountains, loves good food and its preparation, eccentric music, and time in nature. He explores approaches to holistic health for himself and his family and is interested in the intersection of Western science and psychology, Eastern mysticism, and shamanism.
Leif speaks native German and fluent English.
Mallori Ratcliff, MS, BCBA
In 2015, Mallori was voted Idaho Falls, Indiana’s top woman to know for her work with children and adolescents suffering from severe depression and suicidal ideation/self-harm. That same year, she was published in the United States Psychiatric Rehabilitation Association quarterly review, a culmination of research projects and awards she won for her research into personality and behavior. In particular, she has studied addictions and dual diagnoses, including Intellectual and developmental disabilities (IDD) and severe mental illness.
The majority of Mallori’s career has been spent working with neurodiverse individuals and their families. She has worked as a therapist, a supervisor, a consultant, and a program director, developing mental health and drug and alcohol programs in the United States that treated low-income individuals and their families. She has also worked as a direct support worker in the field/community, in the home, in the clinic, in schools and via telehealth. A highlight of her clinical practice has been working with individuals who were dually diagnosed with severe mental health and IDD, helping them to stabilize and lead fulfilling lives.
Mallori speaks native English, some Spanish, and a bit of German.
Miriam Quarterman, RBT
Miriam is a German native born in Heidelberg. She is a mother to 3 children with a background in elementary school education. She moved to the Rheinland Pfalz region during her time as a military spouse and returned after a few years in the frozen tundra known as North Dakota. While living in the United States, she worked as a Support Parent for Early Intervention, served families of children with special needs as a member of the Family Voices of North Dakota, became involved with the Children's Hemiplegia and Stroke Association, and lobbied the governor to establish a national Pediatric Stroke Awareness Day.
Miriam is a mother of an autistic son who survived an in utero stroke. So, she understands the parents' side of Autism. And it was her son who inspired her to become an RBT.
Miriam has a love for food so naturally she enjoys cooking and baking, so much so that she started a small bakery. When Miriam is not working at the center or baking she enjoys spending time with her family, including their dog and cat.
Miriam speaks native German, fluent English, some Spanish, and some French.
Natana Gill, MA, RBT
While studying to be an actor at university, Natana had the chance to teach drama in after-school programs. She fell in love with teaching, finding that she enjoy her students' on- and off-stage successes more than her own. A few years later, when she observed a class at the Texas School for the Blind, she knew she had found her calling. Natana obtained a master's degree in Special Education from Texas Tech, spending the next 8 happy years working with students of all ages with a wide range of abilities, and diagnosis, including autism.
Although moving to Germany has been a wonderful adventure for Natana, it also meant leaving her students behind. She is excited for the opportunity to work with the learners at Teaching Tree Clinic, because in some ways, it feels like coming home. Natana now has nearly 20 years of experience working with children in a variety of roles, not least including nanny, puppeteer, library storyteller, and Mad Science instructor.
Natana loves to read, spend time with her family exploring villages, and learning to weave.
Natana speaks native English.
Samantha Cimirro, MOT, OTR/L
Samantha Cimirro was born and raised in New Jersey, USA. She graduated Summa Cum Laude with a bachelor's degree in Psychology from Stockton University. While pursuing a PhD in Clinical Psychology, she met an occupational therapist at a residential school for children and adults with severe and profound disabilities. She was inspired. She changed course and spent the next 2 years working full-time and taking night classes to qualify for the Masters of Occupational Therapy program at The University of St. Augustine for Health Sciences.
Samantha graduated 2 years later with high honors and proceeded to work with pediatrics to geriatrics in homes, schools, and private and state facilities. As Teaching Tree Clinic's occupational therapist, she intends to continue to expand her training and become a certified feeding specialist. Having struggled with sensory processing differences as a child, especially in the area of eating, gives her the perspective to understand and empathize with what her clients and their family are going through.
These days, Samantha enjoys spending time with her own child and her husband.
Samantha speaks native English.
Sara Melià Carreras, RBT
Behavior Therapist & Office Manager
Sara was born on a small island called Menorca. She has split her time between Spain and Germany for the past 3 years, but she is ready to set down roots in Germany.
Sara studied tourism and, for 5 summer seasons, worked with children as an entertainer. It fulfills her, helping and making families happy, be it as an entertainer or as a therapist.
Sara loves nature, animals, and traveling.
Sara speaks native Spanish and Catalan, excellent English, some German, and a bit of Italian.
Sasha Cress, MEd, BCBA
Behavior Analyst & Onboarding Coordinator
Sasha is military spouse residing in the Kaiserslautern Military Community. She is committed to promoting hands-on learning for children of all abilities and through all stages of the learning process. She believes that every child is a capable learner and deserves a positive and supportive environment to foster their physical, emotional, intellectual, and social needs.
Sasha has worked with children in diverse roles, from early childhood educator to paraprofessional in special education classrooms to primary school instructor. She joined Teaching Tree Clinic as Registered Behavior Technician under the mentorship of Veneta Dimitrova before obtaining her certification as a Board Certified Behavior Analyst.
Sasha holds a bachelor’s degree in Communications from Grand Canyon University and a MEd in Curriculum and Instruction with an emphasis in Applied Behavior Analysis from Arizona State University.
Sasha speaks native English.
Sonia Roach, MA, BCBA
Sonia is military spouse residing in the Kaiserslautern Military Community. She has worked with students ranging from preschool to high school as a para-educator, a Special Education teacher, and now a Board Certified Behavior Analyst. She believes that every child is capable of learning and developing—socially, emotionally, and academically—when provided a nurturing environment. In her experience, these environments entail collaboration with other professionals, including occupational therapists, speech pathologists, and educators.
Sonia graduated with an undergraduate degree in psychology, holds a teaching credential in early childhood special education, and obtained her master’s degree in in curriculum and instruction with an emphasis in applied behavior analysis.
Sonia speaks native English, native Spanish, and a bit of German.
Stephen Buckley, MS, BCBA
Stephen hails from Ireland, and it is there that for many years he lived alongside the children, teenagers, and adults with disabilities with whom he worked as a carer. He found that the people he worked with grew and became happier when they experienced encouragement from carers who showed interest, compassion, and empathy for them. However, he eventually noticed that many of people he worked with also appeared to be “stuck.” Over the years, they did not significantly expand their activities, access to educational opportunities, social circles, or self-help skills. Indeed, they would even regress, like by engaging in self-harm behaviours.
After researching therapies that offered to increase the self-help and social skills of people with disabilities, Stephen learned of a scientifically validated method proven successful with all types of individuals to improve all types of socially significant behaviour. In 2015, he returned to school to obtain a second master’s degree, this time in Applied Behaviour Analysis.
As a trainee, Stephen introduced ABA-based strategies to a large residential centre in Ireland that had come under scrutiny for poor practices, cultivating a culture of Positive Behavioural Support. Since then, his practice has centered on consulting with German families with infants and children with autism.
Stephen speaks native English and some German.
Tenny B. Chalian, MA, BCBA
Senior Behavior Analyst
Tenny has been in the field if Applied Behavior Analysis since 2009. She obtained her Master’s degree in Psychology with an emphasis in Behavioral Clinical Psychology from California State University, Northridge. She worked with individuals with autism and other developmental disabilities at home, school and community setting for several years.
She also has experience working as an Autism Program Specialist at the Behavioral Health Department at one of the largest health plans in Los Angeles.
She believes that teamwork makes the dream work, specially when helping families that have kids with special needs. She loves conducting different types of functional analysis and doing assessments in general.
She is passionate to teach new skills to her clients and make meaningful changes using safe and dignified treatment plans.
Tenny loves to travel with her husband as well as take a long walk or hike in nature and learn something new everyday.
Tenny speaks fluent English, excellent German, and native Armenian and Farsi.
William (Billy) Moulden, MA, BCBA
After earning his Bachelors Degree in psychology, William began working at Eden Autism in New Jersey where he discovered his career. He has worked in the field of ABA for 6 years starting as a Teaching Assistant working with middle school age children. William earned his Masters degree in Applied Psychology focusing on Applied Behavior Analysis at Rider University in New Jersey. He completed his training to become a BCBA at the adult services program of Eden Autism. William has worked with both Children adolescents and adults with a primary diagnosis of Autism from age 6 to 70.
William enjoys baking and going for long walks with his dog.
He speaks native English and some German.