Many of you will be starting the school year this week, and others in the next two weeks. Take a deep breath... You and your child(ren) will be fine. It is going to be a fantastic year!
To help your younger child who is nervous, remind him of the things he likes the most about school: seeing friends, P.E. and recess. Go through what the day would be like... Allowing your child to visualize the next day and have a sense of predictability will surely decrease his anxiety.
For your older children, there will be a mix of anxiety and excitement. Older children are more self-conscious; they will be thinking about things such as how they may have changed physically, or if they will be able to keep up with their school work. Building their self-esteem by reminding them of their strengths and talents can help.
Both older and younger children will benefit from being in contact with friends from school prior to the first day. This again brings a sense of predictability and re-attachment to school.
Lastly, try to get a good night's sleep and a proper breakfast... Good luck!