Hello Shoukoucho55
7 tickets for adults (16+ years)?
The best option is probably a Saver Day Pass, valid for all connections on the day of validity. Save your Saver Day Passes soon, as the price is increasing the nearer the date and the higher the demand. Currently, the Saver Day Pass costs CHF 61, full fare. A regular full fare one-way ticket costs CHF 134 - quite a bargain!
You can find further information on Saver Day Passes here:
https://www.sbb.ch/en/tickets-offers/tickets/day-passes/saver-day-pass.html
For children, you may purchase the Junior Card at 30 CHF per child, valid one year, allows free travel on any public transport service provided the child is accompanied by a parent with a valid ticket. Or, you can purchase for each transfer the Day Pass Children for CHF 19 in 2nd class:
https://www.sbb.ch/en/tickets-offers/tickets/day-passes/day-pass-children.html
Kind regards,
Roland