1) Be polite but do NOT let them in unless they have a signed search warrant.
Why? Never let any officer of the court, including a truant officer, in your home without a warrant, even if they show up with an armed police escort (this is an attempt to intimidate you into admitting them without a warrant). By allowing them to enter you are also allowing them to search your home. If they are looking for any excuse to harass or intimidate you, if you don't let them in you can't give them any ammunition.
A) Make your children unavailable to them. Do not let them talk with the officer.
B) You should say something to the effect of "I'm really sorry you had to come all the way out here and waste your time. I really do understand that you had to come." and then follow it up with "I really don't want to talk to you without a witness (or my attorney). You may wait here until one arrives, or I can meet you at another time with my attorney." Offer to meet them in a public place at some set time with your witness and your children. The public library or the local McDonalds will do just fine.
C) You have the right to ask why they are at your door and what charges they are bringing against you.
D) Ask for their business card so you can 1) remember their name because by now you WILL be in a state of panic and 2) be able to call them right away if you can't find a witness to come with you to the meeting you will set up.
2) If you make an appointment, show up on time with a friend/attorney as a witness. Bring with you the following:
A) A letter, signed by you, stating that you are in compliance with Section 26-1 of the Illinois School Code because you teach in the branches of education in the English language. A sample letter is provided here.
B) A calendar with dates you 'did school' marked off. Always remember that attendance in a school is mandatory in Illinois and that your children are in daily attendance at private school. Your homeschool is a parent-administered private school and they are simply in attendance at home. A truant officer is almost always there to verify attendance so understanding this is very important.
C) Be polite as can be, but if they ask to see your curriculum explain to them that they have no legal authority to approve your curriculum because Illinois has a compulsory attendance law not a compulsory education law.
D) Some will suggest that if you own a video camera or audio tape recorder that you use it now to record any and all discussions with the truant officer just in case there is a later misunderstanding about anything you have said at this meeting that your witness can't clear up.
After handing them the paperwork and letting them see (but not talk to) the children enough that they can be assured they are not abused, get out of there.
Why leave so fast? So you don't accidentally say anything that could be used against you!
3) Be sure to follow up:
A) If at all possible, have your witness write a letter about what he/she witnessed and have it notarized - just in case you get a follow up letter from the person you met with.
B) Many people suggest taking your child to your family physician that same day and having the physician verify in writing that there is no evidence of abuse. If you are accused of physical abuse of any kind this will help you.
C) If possible, send a copy of the letter you wrote to the people you met with by certified mail (return receipt requested) just in case they lose the one you gave them at the meeting.