No, children who live in Illinois do not need to show any ID to visit on a Free Day, as long as they are accompanied by an adult (age 18+) who is a resident of Illinois and has the appropriate proof of residency. Students Students (age 12+) with a valid school ID receive a $3 on-site discount on their general admission every day except Illinois Resident Free Days. This offer cannot be combined with the Chicago resident discount and is not available for child admission tickets (age 3-11). Above is extract from Shed Aquariums website.
For the aquarium children do not need an ID. However as a general rule school ID, birth certificate, medical records, shot records or a state issued id (you can get them at the drivers license bureau). Some places will accept school report cards or school info sheets showing the student is registered.
I agree with Giri
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