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Quality Starts at the Top

To help children with learning disabilities achieve their full potential, you need more than facilities and equipment. You need visionaries with the unique capability to understand the challenges of today and prepare for the needs of tomorrow. At Cove, we’re blessed to work with administrators who can draw on their diverse experience to give our students the singular resources they need to succeed.

Our Administrative Team

Sally L. Sover, Ed.D.
Executive Director

In addition to a doctorate in education, Dr. Sover brings more than 20 years of practical field experience to her role as the Cove’s Executive Director. Prior to accepting her current post, Dr. Sover held several academic and administrative positions in School District 300, including district literary supervisor, district curriculum and instruction leader, literacy teacher leader, and special education teacher. In addition to her work with the Cove, Dr. Sover has also served as an adjunct faculty member of Aurora University in Aurora, Illinois.

Robin S. Johnstone, Ph.D., NCSP
Clinical Director

Dr. Robin Johnstone is a certified school psychologist with a doctorate in learning disabilities from Northwestern University in Evanston, Illinois. Once a teacher herself, Dr. Johnstone has invested her entire professional career in educating children with learning disabilities.

Mr. John Stieper, III
Director of Education

Mr. Mark Ditthardt
District Liaison

Mr. Mark Ditthardt has a masters degree in social work with additional certifications and endorsements as a School Administrator and Director of Special Education. For the last 26 years he has worked with the Winnetka Public schools, serving first as a school social worker then as the Director of Student Services for the district. As the director of Student Services he had responsibility for the development of all aspects of the District’s special education services and related services to students with a variety of disabilities. He has also served as the liaison to all of the schools outside of the District in which the District had  placed students. 

Academic Advisory Board

Doris Johnson, Ph.D.

Dr. Johnson is the Jo Ann and Peter Dolle Professor Emeritus in Learning Disabilities at Northwestern University where she has spent most of her career. She has long been interested in the relationships between oral language and higher levels of learning including reading, written language, and mathematics, as well as learning disabilities across the life span. Professor Johnson continues to teach courses at Northwestern and coordinates the Adult LD clinic. For the past three years, she has participated in an early literacy project with Head Start children in the Chicago Public Schools. She has enjoyed working with people from Cove School over the years and is pleased to be a member of the Advisory Board.

Jo Ann Hoeppner, Ph.D.

Dr. Hoeppner is a neuropsychologist who has worked as a consultant with The Cove School since 1995. Dr. Hoeppner holds a PLD in Perception and Cognition from the University of Waterloo in Ontario. She joined Evanston Northwestern Hospital in 1973, and was Director of the Evaluation Center between the years of 1992 – 2006. She has held a private practice since 2006. Her special interests lie in seizure disorders and learning disabilities.

Pearl Rieger, MA.

Pearl Rieger is well known throughout the community as a psycho-educational diagnostician who was one of the founders of the Rush Neurobehavioral Center. In her private practice, Ms. Rieger has worked extensively with students, families, and other educators to better understand the challenges facing children with special needs. For the past five years, she has trained Post Doctorate Fellows.

Warren D. Rosen, Ph.D.

Dr. Rosen specializes in understanding the interplay between neurocognitive, emotional and social features in children and adolescents with a variety of neurological diagnoses, including learning disabilities, attention deficits, seizure disorders, and neurosocial disorders. Drawing from theories of neuropsychology, family systems, and socioemotional development, his private practice centers on diagnostic assessment and therapy. Dr. Rosen obtained his clinical psychology doctorate from Georgia State University, and he completed his internship and post-doctoral fellowship at Harvard Medical School’s Children’s Hospital and Judge Baker Children’s Center in Boston. He is an assistant professor at Rush-Presbyterian-St. Luke’s Medical Center in the Departments of Psychology and Pediatrics, and he has taught at the University of Texas, University of Houston, Institute for Clinical Social Work, and Loyola University. Dr. Rosen is a member of the academic advisory board of the Hyde Park Day School, and of Men for Shalom {Peace} in the Community and Home (MenSCH), a grass roots organization of men educating adolescent and adult males about domestic and interpersonal violence and intimidation.