Museums should be free like in London.
It's cheaper if you are a chicago resident. But normally the tickets are kinda pricey. But it's worth going to see.
If you're a Chicago resident tickets are half price
$38 with 3d ticket
The mommies is a ticketed exhibition. You'll need the $38 ticket for that. It also includes access to 3D movies. The basic ticket is $24 but that's without ticketed exhibitions or 3D movies. Also check Groupon as they have deals sometimes
Check the website. There's also city pass.
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