You should ABSOLUTELY be able to register your daughter in high school.
Below is a link the the Illinois State Board of Education Registration Guidance for the 2012-2013 School Year.
The Registration Guidance should allow you to register your daughter under either section (i) or section (v).
Section (v) is a "catch all" provision that covers situations not otherwise covered in sections (i) through (4).
You may wish to print out the Registration Guidance and present it to the school in which you want to register your daughter.
Moreover, the Registration provides a hyper-link to an Affidavit that you may wish to fill out, if necessary, and present to the school.http://www.isbe.state.il.us/pdf/guidance_reg.pdf
I hope you find this information useful.
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