Traveling with family

Hi

I am planning a trip to Japan from november 9th till the 26th with my husband and 9 year old son. We are going from tokyo to Kanazawa, Takayama, Kyoto, cycling the Island for 2 days Shimanami Kaido
Cycling route across the Seto Inland Sea and OSAKA to then go back to Tokyo. ( total 18 days )

I was wondering if you think that the JR pass is worth for this trip and are there children prices?

Thanks
Care