They will accept a driver's license or government issued ID. They can you look you up in the system. You do not have to have your Children's Museum card. They can look you up in the system. I know this because I almost never have my Children's Museum card and they look me up almost every single time. Also some unsolicited advice, if you want to do a free cooking class, head upstairs immediately to the Teaching Kitchen. The sign up sheets for the entire day are put out as soon as they open and the first three classes usually fill up by 9:30. We've done 20+ classes, they are wonderful!
The pass and your ID, I would think. Maybe call them and ask before you go, just to be sure.
Am so sorry I can't answer your question because I don't live in Denver.
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