There's nothing wrong per se with governors visiting classrooms. They are so accountable these days, that they need to have a good awareness of what is going on in school. What is important, is why governors visit classrooms, and how the visits are carried out. Our governors visit to see "their" subject being taught. They liaise with the subject co-ordinator who lets us know which governor is visiting and when, and asks for volunteers who are happy to have a governor see their teaching. So we always know when a governor will be in our classroom. Governors always make a written report which they send to the SMT and relevant subject co-ordinator. They know that they mustn't comment on teaching and learning as they aren't qualified to do so. But they will describe the kinds of activities they saw happening in different year groups, and comment on things such as how engaged children were. All the reports I've seen have been very positive, and have included a request to pass on their thanks to class teachers for letting them see the lessons. If governor visits are carried out like this, then they are useful in terms of developing governors' understanding of what happens in school, and in developing good relationships between staff and governors. If governors drop in unannounced, or are asked to make (or to assist in making) judgements, then that is a completely different story.