If I claim my two children, why is federal withholdings not being deducted?

[VolvoGirl]

On your tax return or deducted from your paychecks?  It's possible that your income is low and they won't take any withholding out.  Give your employer a new W4 to have some taken out.  

On your tax return claiming children doesn't affect the withholding on 1040 line 25a or 25b.