The education of a child should be a partnership between teachers and parents. Both should clearly understand the expectations for the child. Both should be instructing and correcting the child with the same set of guidelines. If your child is having behavioral problems in school, the first thing to do is to contact the teacher and get a complete understanding of the expectations for the school day and where the child is missing it. Misunderstandings in any human interaction make for rough social exchanges; take this out of the equation.
Make sure your kindergarten student is adequately prepared for each school day. Ensure he gets a proper amount of sleep the night before and eats a nutritious breakfast to give his body the fuel he needs to perform well. None of us perform well when we are sleep-deprived or hungry. Lastly, provide ample time to get dressed and to school. A frantic rush to get to school in the morning may only promote agitation and anxiety which can translate into behavioral problems in the classroom.
Often our lives are so hectic that many homes lack any type of routine children can relate to. Therefore, when a routine is thrust upon them with requirements far greater than ever required before, children can react in negative ways. Establish a routine at home that provides adequate active play time to allow children to burn off excess energy (before school, if necessary) and create quiet times for the entire family to abide by. In addition, develop and discuss kindness rules as a family to reinforce learning to be kind as well as respecting other people verbally and physically.
Perhaps the most commonly used tool in working with behavioral problems is using a reward system for good behavior. Use positive statements each morning like, "I can't wait to hear how good you were when you come home from school today." Reward good reports with treats like special play time or a favorite dessert at dinner. When your kindergartener doesn't have a good day, talk over what is expected of him in a positive manner -- explaining the good outcomes of good behavior. Be consistent in your reactions and make eye contact during your discussions so no mixed messages are sent to the child.