Your son may be liable to pay into the Social Security and Medicare system by paying self-employment
tax:
Special rules apply to services a person performs as a newspaper carrier or
distributor. A person is a direct seller and treated as self-employed for
federal tax purposes if he or she meets the following conditions:
Carriers or distributors (not including those who deliver or distribute to any point for subsequent delivery or distribution) and vendors (working under a buy-sell arrangement) who do not meet all of the above requirements and are under the age of 18 are generally not subject to self-employment
tax.
Form 1040, Schedule SE (PDF),
Self Employment Tax, must be filed if net earnings from self-employment are $400 or
more.
Self-employed persons report their income on
Form 1040, Schedule C (PDF),
Profit or Loss from Business (Sole Proprietorship), or the person may qualify to use
Form 1040, Schedule C-EZ (PDF),
Net Profit from Business.
If you were self-employed, you can deduct one half of your self-employment tax
and part of your health insurance premiums.