The Earned Income Credit (EIC) is calculated by the program automatically if the return qualifies for the credit.
To remove the credit from a return that qualifies for it, you need to enter information that will disqualify you (paid preparers can just override the EIC amount). Keep in mind, the IRS may question why a return that qualifies for the credit does not contain it.
To disqualify your return from the Earned Income Credit in the TaxAct program: