Unfortunately, kids may not be able to recognize and articulate what they are feeling. Alternatively, as they get older, they may not be willing to share what they are feeling with us as their parents. Your child may be experiencing stress and anxiety that you don't even know about.
Physical anomalies. Have their sleep patterns or eating habits changed? Do they say they are feeling sick or are behaving in atypical ways?
Loss of independence. As the school year approaches, are they getting more "clingy"; are they asking you to stay with them when they would otherwise want to be on their own? Have they verbalized concern about making friends?
Consult with your child's martial arts instructors or coaches. Martial Arts instructors or coaches are often a valuable "in-between" mentor. They don't feel as authoritarian as a parent or school teacher might, yet they still command trust and respect of their students. Check in with them and find out if they're noticing any differences in the martial arts studio or on the practice field.
The 5 key things that you can start doing now:
If possible, visit the school ahead of time. Even one layer of familiarity will help to reduce the anxiety and nervousness. While you're there, let your child know about the opportunity to meet new friends, and that they'll have new, fun experiences
Check yourself. Don't let too much of your own stress and anxiety show. If you are nervous about them starting school, they will possibly feed off of your emotions.
Reach out to other students that will be in the same school or class and arrange play dates or other social interaction. Going into school already knowing someone or having friends is a big stress reliever (for you and them)
Routine. Confidence is derived from competence. And, competence is derived from repetition. Anxiety also comes from fear of the unknown. Establish a regular and effective set of daily routines: morning, after school, bedtime. This will automatically reduce logistical stress of "getting ready", and give them the confidence of having a plan and knowing what to do every day.
Acknowledge their anxiety. Say something like, "I know you're feeling a little scared about starting school, right now, but that's ok." This does two things. First, by recognizing their feelings they will know that you are on their side. Second, it helps them understand that feelings are a temporary condition, and they will pass.
Prepare for the start of school with the right tools.