My son indicated that he could not be claimed by anyone else as a dependent, he still lives at home and was a full-time student, can he amend his taxes after submission?

[SusanY1]

Yes, he can still amend his return, and he should do so.  

If you wish to e-file this year, you can only do so by getting an IPPIN from the IRS.  Once you have the IPPIN you can e-file but you'll need to remember to retrieve your new IPPIN each year from the IRS system for electronic filing going forward.

Alternately, you can print and mail your return this year.