It depends.
I won a $5000 scholarship myself before USNA. If you take it to Navy Federal, you could probably deposit that money right into his personal account just like I did after plebe summer. USNA would not integrate that money into his issue because that is broken incrementally and equally for each midshipman. In some way, he should see that money whether it be through his savings account at Navy Federal or slightly increased pay each month...good question.
