Yes, you should be able to claim him.
A child of a taxpayer can still be a “Qualifying Child” (QC) dependent, regardless of his/her income, if:
1. He is under age 19, or under 24 if a full time student for at least 5 months of the year, or is totally & permanently disabled
2. He did not provide more than 1/2 his own support. Scholarships are considered third party support and not as support provided by the student.
3. He lived with the parent (including temporary absences such as away at school) for more than half the year
How do you do it? Just go thru the standard dependent interview. Answer 8 months when asked how long he lived with you.
However, there are three more rules:
4. He must be a US citizen or resident of the US, Canada or Mexico
5. He must not file a joint return with his spouse or be claiming a dependent of his own
6. He must not be the qualifying child of another taxpayer. So, for a common example, he lived with the other parent for more than the 8 months he lived with you. He is the qualifying child of the other parent and you can't claim him without permission from the "custodial parent"