JR pass worth it or just regular train tickets

Our family of 4 (2 adults and 2 teens) will be travelling to Japan next summer. This is our itinerary:
Tokyo for 3 nights ( travelling around Tokyo to visit major temples and sites) then
Kyoto for 2 nights (visiting temples and bamboo forest and possibly to Nara for the day) then
Osaka for 1 night and fly out from Osaka.
I know it cost $125 one way from Tokyo to Kyoto on the Nozomi train, but how about from Kyoto to Osaka and Osaka to the Kansai airport? Will the fares be that expensive to travel locally?

Any feedback would greatly be appreciated.
Thanks.