You can send a Mail Merge email from the Communications area by searching in the To box.
This method of communication will include those who were Club Participants but have now cancelled their membership.
To communicate with just current Club Participants, please see Emailing Guardians from a Club.
Paid clubs - the list of Club Participants will show those who have cancelled their memberships.
Free clubs - the list does not show cancelled memberships, as there are no invoices to track. But the student will still be considered to be on the list of Club Participants in the background.