He said when they brought this in the rate of vandalism dropped significantly and the pupils developed and responded.
"They were a neat bunch of kids who faced a lot of difficulties but we made school a secure and happy environment for them."
Two weeks ago the students came together and showcased their cultural talents with songs, a waiata and a haka for Mr Watson. They presented him with a waka huia the children had designed themselves. They wrote statements about him and then Hugh Tareha created the piece of artwork.
Mayor Lawrence Yule, representatives of the police and former students all attended the farewell and celebrated his success.
The retired principal said the years he spent at Camberly were some of the best and he had made some "wonderful" memories.
"One time a student ran away from the classroom so I decided to get in my car and drive to his house to beat him home. Just as he walked up to open the door he looked up and there I was."
Mr Watson was overwhelmed with all the support he had been given and said he would spend the next months being a "housewife" before doing voluntary work.