Here is the link for a free school ID for homeschoolers. You simply print this off yourself, and if you want you can laminate it.
Of, if you would rather, you can order a paid hard laminated copy of it.
A school ID card often gets you discounts on admissions and stores and restaurants where they offer a student discount.
You can also order one for yourself as the teacher, for the places (such as Michael's and Office Depot) that offer a teacher discount.
There are a few places that like to argue about homeschooling. This is one reason why our cards list the name of our school as Countryside Christian Academy instead of saying Homeschooler.
Check out this co-op site--it is free to join and they offer many free things and discounted things for homeschooling families.
A reader also sent in this site as well-- it is another source for a free ID card.