Colleagues were extremely valuable to me throughout my career. Colleagues are able to influence you in many different ways on a daily basis. Fortunately most influence is positive,but there was the odd negative result.
Teachers gain so much from each other by cooperating. They have so much to learn from each other and the students are the ones who benefit. I enjoyed working with people to put together units or to outline a full year program. In that way we did not have to reinvent the wheel. One wheel could be built with many more parts to make it a better wheel. It would take much time for one to create a unit, but together complete units of work could be put together with much more detail.
Early in my career I was fortunate enough to work in a team teacher situation teaching science. When you team teach it is important that all details be planned so that all material is covered in a similar manner. Evaluation was also prepared so we really had to cooperate.
I also was able to learn many skills by watching my colleagues. Sometimes we organized formal lesson observations, but may times this learning was incidental when you would walk through a classroom or by listening to someone explain a procedure they used and you could take it and adapt it to your own situation. Many small tricks of the trade were shared. Many times I needed some moral support and it would come from fellow teachers . I guess many times people could tell if you were down or struggling with something and needed a little moral support.
I also enjoyed having student teachers. I usually felt I had something to gain from them as they were coming out with some of the latest methods. They needed a chance to put some of their ideas to practice. They also had to watch me and again saw some of the old tricks.
I have been retired for twelve years and meet former colleagues regularly. These are good times that we enjoy.