Test for university's entrance examination

I send a mail for my high school's junior yesterday. Now, they are senior in high school and candidate. In my mail, I said that try your best and bless you! I want to go their test well for them. I experienced same thing two year ago, so I know that it is tired, troublesome and importance of motivation. I wanted to tell that and I want to they didn't make their cold. Some of them gave me answer mail for me today. They looked healthy, so I was happy. (90 words)