Did you contribute to a 457(b) plan?
The 457(b) plan is a type of non-qualified, tax advantaged deferred-compensation retirement plan that is available for governmental and certain non-governmental employers in the United States. The employer provides the plan and the employee defers compensation into it on a pre-tax basis.
That contribution would go on a Form 8880 (Credit for Qualified Retirement Savings Contributions) when you file your taxes. There is no spot for that credit to be entered on a 1040EZ.
The Form 8880 credit will go on Line 34 of a 1040A or on Line 51 of a 1040.