It may be that your child’s teacher is too busy to deal with children who are more prone to expressing their emotions in this way, but if you speak to her you should be able to explain your point of view. Tell her that you think it’s perfectly normal for your child to cry if he wants to (which it is) let her know that it’s okay to leave him to cry, and that it will help him to deal with whatever is bothering him.
Some schools will take a harsher line with crying, and they may see it as more of a problem. If you have a sensitive child, you have the option of seeking another school that’s more understanding, or you could spend a few minutes with your child, before and after school, where you ask questions about how he is feeling, whether anything is bothering him and so on.
Often, crying over minor things, like spilling or breaking a biscuit, can be have nothing to do with the event itself, and is simply a reaction to a bad day in general. Sometimes it’s a symptom of missing you and your partner at school, and sometimes it’s a reaction to a completely different problem in your child’s life.
Boys, in particular, who are taught from a young age that crying is not okay, may find ways to hurt themselves physically so that they are ‘allowed’ to cry.
If it is becoming a constant problem, then speak to your child’s teacher, and arrange a meeting where you can both sit with your child, discuss any problems, and come up with a solution.