The school traces its roots and foundations back to the Queen Victoria High School, which was founded in Stockton in the nineteenth century. These buildings no longer survive, but the site was opposite St Peter's Church on the Yarm Road in Stockton.
The Cleveland School was founded in 1938 but moved in 1945 to the rambling mansion of Woodside Hall on the beautiful banks of the River Tees in Eaglescliffe. These impressive buildings were enjoyed by generations of schoolgirls before their demolition in 1970.
At this point in time, the two schools merged, the name Teesside High School was adopted, and the present buildings were begun. Since then, the school has flourished under several distinguished Heads. Both of the pre-merger schools were girls' schools. However, in 2005 Teesside High School made the decision to admit boys for the first time in the Prep School, and in 2008 they first enrolled in the Senior School and Sixth Form. This year, 2015, the school marked the occasion of 70 years of education on the current Eaglescliffe site with a celebratory lunch. It was heart-warming to hear so many tales and stories from pupils who attended so long ago, and particularly at the time when the school first moved here in 1945.