What can I do to get my son to stop craving for attention?

Thank you for reaching out! 

It can be so difficult when our children are struggling, and finding ways to help them can feel exhausting; I appreciate you taking the time to look for support around this issue. 

If the school did not already suggest this, it might be helpful to start by having a meeting with his teacher(s) and perhaps school guidance counselor or social worker to see if there is a way to help with this behavior in school.  Typically, schools are able to implement additional supports or structure to help children reduce a behavior in that setting.

If you are finding that punishment or discipline methods you are using are not effective, perhaps focusing on building in one on one time with your son might help over time.  I'm sure you spend lots of time with him throughout the week - it might be helpful to try and structure some of that quality time into doing specific activities; this might allow for your son to feel that he is getting some more of that 'attention' he is looking for.  Another helpful strategy could be to focus on positive behavior - praise him every time you notice him doing something that you want him to be doing behavior-wise; this positive praise and reinforcement could help over time with reducing negative behaviors.  

For some children, it can also be helpful to implement a behavior incentive chart.  A behavior chart functions to help set a goal (example: if the primary issue is getting up and walking out of class, the goal might be something like "remain in class all day" or "ask permission to leave the classroom").  You would then create a chart that clearly describes the goal, and mark off with stickers or checkmarks each day that the behavior has been successfully displayed.  At the end of the week, some parents choose to provide a small reward to reinforce the behavior.  The reward or prize can be simple, such as a half hour extra of video game time or letting your child pick the movie for family movie night.  There are lots of free resources online that provide templates and examples of behavior charts for children.

You might also decide that seeking therapy or counseling for your child would help; sometimes, bringing in a professional to help can be effective in figuring out the root cause of the behavior and finding appropriate ways to support the child and mange the behavior.