jQuery Ajax checkbox value

I have checkboxes on my page for which I would like to send their state back to the database via ajax. I know how to use jquery with ajax and how to work with SELECT and OPTIONS, but I don't know to do the same things with several checkboxes and how to get the value from them. Everything works when id is attached to one checkbox, but when i attach id to several checkboxes it doen'twork(except first check box)

Any ideas?