Simply replace the unfilled areas such as "" and "[date]" with your information.
Dear [Principle/ School Official],
We are writing to express how pleased we are with the great experience our [son/daughter], [Child's Name] has had with [Mr./Mrs/Miss] [Teacher Name] this school year.
We are amazed at the positive effect [he/she] has had on our child. In previous years, [Child's Name] had issues with [previous issues]. However, this year [he/she] seems to be a different, better student. We attribute [his/her] success to [Mr./Mrs./Miss] [Teacher Name]. [His/Her] ability to reach [Child] through [teaching techniques] has helped our [son/daughter] succeed like never before.
It is important that [Mr./Mrs./Miss] [Teacher Name] be recognized for [his/her] superb teaching abilities. All students deserve such a [adjective] and [adjective] educator.