To feed your BigSIS Calendar into ParentSquare, all you need is an ICS file. Whenever you make a Calendar Feed, BigSIS automatically makes an ICS link for it.
First here's how to Create a Calendar Feed.
From the Feed, all you need is the Access Url.
NOTE: Sometimes, ParentSquare has trouble with these ICS links, but changing "webcal" to "https" at the beginning of the Access Url should take care of the issue.
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