St. Catherine’s Montessori was founded as Dominican Montessori in 1966 by Sister Edna Ann Hebert, O.P. and was joined the next year by Sister Shirley Owens, O.P., both Dominican Sisters.  The school was established to serve families searching for quality educational and religious programs responsive to the individual needs of the child.  Dominican Montessori was the third Montessori school in Houston and the first Montessori school to include basic Catholic doctrine in its curriculum.  Sisters Edna Ann and Shirley both held diplomas from the Association Montessori Internationale (AMI).  Sister Shirley remained on the Board of Directors until she passed on in June of 2012 and Sister Edna Ann currently serves on the Board of Directors in an Emeritus position.
St. Catherine’s Dominican Montessori began in the original St. Agnes Academy building and remained there until the building was sold in 1974.  Dominican Montessori then moved to the Holy Rosary Parish housing the Primary classes and later expanded into another building at Bering Memorial Methodist Church where the Elementary classes were located. The school formed a non-profit corporation in 1974 to receive and maintain funds for educational purposes.
In 1983 the school moved to 2510 Westridge into a building that had been an arms museum and looked like a castle. Dominican Montessori was re-named St. Catherine’s Montessori after St. Catherine of Siena, a Doctor of the Church and Dominican Sister and dedicated follower of the Dominican way, acclaimed for her preaching in the fourteenth century.  At this location the school expanded to include upper elementary and in 1997 a middle school was started.  In 2002 the ninth grade was added and now called the Adolescent Community.
In August of 2006 St. Catherine’s moved into its newly constructed 39,000 square foot current home at 9821 Timberside.  The building was the first Leadership in Educational and Engineering Design (LEED) certified K-9 school in Texas.  St. Catherine’s is on 10 ½ acres which includes a soccer field, pond, orchard and many class gardens.  The new location also afforded an opportunity to add a toddler class with the school now serving children 14 months to 15 years old. 
In 2012 St. Catherine’s added a third lower elementary class and second upper elementary class to join the one Infant Community class, four primary classes and one Adolescent Community.