I am complaining because (give as much detail about the incident. Include the date/time, people involved, what happened, any witnesses).
So far the following actions have been taken: ( explain what happened so fa in response to your concerns e.g meetings, actions by the school. You can include references to emails or any form of recorded communication).
I would like you to put things right by (e.g offering an apology, changing school policy, giving my child extra help).
I would like you to investigate this matter further and let me know of the outcome ( You can put a time deadline here)