Our Story

The Mission


For more than ten years, the nationally acclaimed pre-K curriculum, The InvestiGator Club®, has produced extraordinary results in thousands of preschool classrooms. Now at last, the very same adventures, music, and enchanting characters are helping families prepare kids for kindergarten.


At Dilly’s Tree House, our goal is to inspire ALL young children to learn and discover through active play and investigation, whether they attend preschool or not. We are thrilled to present the premier family engagement program that empowers little superheroes by building the confidence and skills they need to ensure positive school experiences.


Dilly’s Tree House helps kids develop kindergarten readiness skills, such as vocabulary, numbers, letters, shapes, and colors, but our vision is much greater than that. We focus on growing superheroes because we believe that all children, regardless of their backgrounds or circumstances, have within them a unique set of strengths and abilities that can launch them to a lifetime of success. Our mission is to help boys and girls discover and build their own powers.

Watch this video to get an inside look into an InvestiGator Club classroom.

As a special education and kindergarten teacher, Judi was known for her commitment to meeting every child’s unique needs. Her early passion to design innovative learning materials led to her career as the co-founder and CEO of Rainbow Educational Concepts and Robert-Leslie Publishing with her husband and partner, Jamie Coffey. Judi believes that her greatest inspirations come from family life with Jamie and their three amazing daughters, and now the pure joy of life with four young grandchildren. Dilly’s Tree House is grounded in solid scientific research and expertise. But more than that, it is a family project filled with energy and love. The entire Coffey family participates in the creation and testing of Dilly’s Tree House. We strive to deliver the message to children everywhere that they are strong and mighty — indeed they are superheroes that can make their mark in the world.

The materials, practices, and activities in The InvestiGator Club® were proven to significantly improve student learning in independent studies conducted by the Educational Research Institute of America. The research was conducted with over 500 pre-K children in 30 classrooms in 11 states. Download PDFs of the full Efficacy Study and Research Report below.

The Preschool Curriculum Consumer Report published by The National Center of Quality Teaching and Learning (NCQTL) was written to help Head Start programs choose high-quality, research-based, comprehensive preschool curricula. This report gave The InvestiGator Club® the highest possible rating for having solid, high-quality evidence in the following categories: Grounded in Child Development Principles, Well-Designed Learning Activities, and Family Involvement Materials.


Research-based activities and components in Dilly’s Tree House give families the tools they need to get kids ready for school by building essential cognitive, social-emotional, creativity, and physical skills.

Dilly’s Tree House was created by moms and educators and tested by kids, parents, grandparents, and teachers.

Rainbow Educational Concepts, co-founded by James and Judith Coffey, has been developing educational products published by major publishers, such as McGraw-Hill, Pearson, National Geographic, Houghton Mifflin Harcourt, Scholastic, and others since 1985. Millions of students around the world have learned reading, writing, math, social studies, and science with the highly successful textbooks that Rainbow helped to create.

In 2005, the founders of Rainbow Educational Concepts formed a new company, Robert-Leslie Publishing, to create early learning products grounded in developmentally appropriate practices, scientific research, and standards approved by state education departments and early childhood organizations. Our mission was to create inquiry-based programs that would foster communication and engagement among all the teachers and caregivers in a child’s life.

In 2006, The InvestiGator Club® Prekindergarten Learning System was introduced to pre-K classrooms nationwide. Products now include curricula for birth through kindergarten, which are used in public and private schools, as well as homeschools, special education, bilingual, and faith-based classrooms.

The InvestiGator Club® and Dilly’s Tree House have received numerous prestigious awards. The curriculum has been endorsed and approved for public and private preschools by state departments of education and early childhood organizations nationwide.

Our little superheroes have played hard to help us discover joyful learning activities your child will love. Our entire team is excited about sharing the fun. We are ready to start delivering boxes of happiness to little superheroes everywhere. So from our family to yours — have a Dilly of a Day!