Ten bucks is low for a whole family event.
You can park in the science center but you have to pay. To me, since the museum doesn't charge admission I don't mind.
I find street parking
If you enter from the main part of forest park they have parking at the planetarium for free (that's the weird shapes building on the north side of I-64). Both buildings (main science center building and the planetarium) connect via sky walk over I-64. Otherwise street parking is free in forest park and you can just walk to the planiatrium entrance. That's the side we always enter on. Been going for years and NEVER paid for parking, honestly I didn't know there was a paid lot.
Plantutriam is free parking
Parking is $10.
They have an area to park in you have to pay not sure of cost we took an uber
They have parking there for 10. You can park on streets but ask you to. Please use theirs. The day we went since we were there until they closed parking was free
They have a lot for $10, but some people get street parking nearby for less (I think free)
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