You can try your local public library for discounted passes. Free passes are available to certain corporate employees. I know MGH provides free passes.
If you have a zoo membership, that's how I got my free tickets.
I would check your local library....mine doesn't offer free passes but they do offer discounted passes. Which after this year, I'd gladly pay to help keep these places from shutting down!
If you live in Boston at the Boston library you haves to have a library card they only give you 4 tickets and they make you pick a day and that’s the day you gotta go at anytime.
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