Michael Ellis, 66, introduced computer studies to Sandhurst School in 1972 and was also involved in leading Scout groups in the town before moving away from the area.
He was on his way home to Bitterley in Ludlow, Shropshire, yesterday (Thursday) morning when he was caught in a fast-flowing stream that had swollen rapidly following heavy rainfall that day.
Mr Ellis was found by police and firefighters following an extensive search but they were unable to save him.
His wife Judith said: "He was a gentle, caring man, quiet and quite shy, with a quick wit and a wonderful sense of humour. He was the most wonderful husband.
"He was truly my other half and I don't know how I can be without him.
"We married in 1973. At the time we were both teaching in Sandhurst and he was leading Scouts and I was Guide leader, so it was natural for us to work together.
"He set challenging activities for my guides at camp and this continued after we moved to Shropshire.
"He supported me in everything I did, encouraging me to take a bigger part in international guiding and accompanying me on visits to Cyprus, Kenya and Canada."
Originally from Barnsley, South Yorkshire, taught at a number of schools and became a deputy headteacher at Ludlow School.
Mrs Ellis added: "He was passionate about maths, with endless patience for those less able but thoroughly enjoying the challenge of brighter pupils, introducing early entry to O Level and GCSE and then teaching those who passed the equivalent of a current AS Level, called Mathematics Applicable."
A post mortem examination was due to be carried out today (Friday) before a formal identification on Monday or Tuesday.
Torrential rain caused flash flooding in many parts of the country, where 50 firefighters from Shropshire Fire and Rescue Service helped people whose homes or roads were flooded.