My 2 sons worked jobs this summer.
1. One worked for a cleaning service where they took out taxes. He earned 1,160
2.The other worked for the school and they did not take out any taxes. He earned 1,265 + 600 for grass mowing. Also Do we add their income to ours or do they need to file separately. Both are students and the oldest turned 18 this past November. Thanks

You can still claim them as dependents on your joint return and no you don't add their income in with yours. Check your state taxes and see if they can file their state taxes and receive a refund on the state taxes - some states let them do this. In Ohio my son could file his own state taxes and receive a refund even though I legally claimed him on both Federal and State filings.

You can claim them as dependants as long as they lived with you the entire year regardless of how old they are as long as they did not make over $3,500 that year.

Did they get W2 or 1099 forms for the income? If so, they should file a return.

Yes, they both received W2 forms.

Neither child has a legal obligation to file their own tax return.

However, the son who had federal income taxes withheld SHOULD file to get his money back. Make sure he does NOT claim himself on the tax return. This can be done quite easily on TaxAct.com or Turbotax.com, and it will be FREE.

The state returns should be filed as well to get the withheld state taxes back. Some state tax MAY be owed (not sure since you did not identify the state).

If you are having your return done by a tax professional, give HIM/HER the W-2s and let HIM/HER handle it. They probably will not even charge you to produce your son's tax returns.

Yes, AtlantaTaxExpert is correct. Your sons don't meet the filing requirement. They will file only to get refund of taxes withheld. If they are dependents, then they will file as Single Dependent that is they won't get personal exemptions.

You can't included your sons' earned income in your tax return. They must file separate tax return.

Noted!