In order to reflect the personal message written for students, you can add some small comments.
take for example
1 The teacher saw your efforts and your progress. Keep working hard, and you will definitely surpass others!
The teacher thinks you are particularly smart and have a good memory, but you should remember that diligence is more important than talent!
Because you are smart, the teacher will ask a lot of you and pay special attention to you. If you relax yourself and regress, I will severely punish you!
The following is my personal opinion. When I was at school, there was a beautiful young female teacher who taught English. She rewarded the top three books, and some sensitive students began to alienate the teacher. So while encouraging the top three, please ask the teacher not to forget the students with average grades.
Generally speaking, it is better to be short and concise, because the teacher has only sent it to the top three, and the information written is particularly sensational and touching, which may make the rest of the students feel that the teacher is biased.