Why do you need my Social Security card?

To prevent identity theft, the IRS requires that all Volunteer Income Tax Assistance (VITA) programs verify the identity of the people they're helping by checking a photo ID and viewing a paper copy of a Social Security Card or Individual Taxpayer Identification Number (ITIN). Alternatively, you can provide an SSA letter or Form SSA-1099 from the Social Security Administration.
If you are filing with FileMyself or another online tax filing service, you will only need Social Security Numbers but not the actual Social Security card.