OurCal's calendar shows events based on both calendars and members. If you've selected specific calendars but are still seeing everyone's events, it's likely because all members are still selected too.
By default the filter mode is set to "or", which means it shows events that match either your selected calendars or your selected members. So if all members are ticked, you'll see all their events regardless of which calendars you've picked.

To fix this, you have three options depending on what you're trying to do:
Tap "Unselect All" under the Members section so no members are ticked. Only the calendars you've selected will be used to filter events.
Tap "Unselect All" under the Calendars section so no calendars are ticked. Only the members you've selected will be used to filter events.
Select the calendars and members you want, then tap the "or" dropdown to choose your filter mode. "Or" shows events that match either the selected calendars or the selected members. "And" shows only events that match both — e.g. events in the "Kids" calendar that are also assigned to "Annie".