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3. Other events like CCS and higher-level squares classes have chosen to use the voluntary-contribution-based model, but the other options above are also available if the event organizers choose to do so. This process does not involve any paperwork, but restricts what Tech Squares/the dance organizers can say about pricing, but does not restrict what the caller can say. (As a side note, the term "donation" is not allowed.)
There's also an email (and GDrive document) "Changes in Money Collection at CCS-like events" that Veronica sent to the officers' list in June 2016 that talks more about some of the options.