Simply replace the unfilled areas such as "" and "[date]" with your information.
I am in need of your assistance in a very serious matter. [First Name] [Last Name] is a student in my [number] period [subject] class. For the last [time period] I have been having increasing difficulties with [him/her]. [He/She] has been [specific issue].
I have contacted [his/her] parents and we have held a conference to discuss the issue. We have not able work together to address the problem. [His/Her] parents have complained that [complaint]. As we cannot reach an agreement, I feel that [Child]'s educational success is in jeopardy. This problem is also affecting the rest of my class. I am asking that you please step in to help us find a solution.