I own a 2nd home and my son lives in it. He pays a portion of the house payment. do I need to claim this as income?

Yes. It is termed a Rental Not-for-Profit. 

Not Rented for Profit

Where to report.   Report your not-for-profit rental income on Form 1040 as Other Income. If you are filing Form 1040 and you itemize your deductions, you can include your mortgage interest and any qualified mortgage insurance premiums (if you use the property as your main home or second home), and  real estate taxes on the appropriate lines of Schedule A (Form 1040). You cannot deduct a loss or carry forward to the next year any rental expenses that are more than your rental income for the year.

Presumption of profit.   If your rental income is more than your rental expenses for at least 3 years out of a period of 5 consecutive years, you are presumed to be renting your property to make a profit.

More information.   For more information about the rules for an activity not engaged in for profit, see Not-for-Profit Activities in chapter 1 of Pub. 535.