Tokyo, Kyoto and side trips

Hello, we are a family of 5 (kids are 13,15, and 17 years) travelling to Japan in June/July 2014. We arrive at Narita Airport on Saturday June 28. We are staying in Tokyo from June 28 till July 3. We plan to see Tokyo and also take a side day trip to Hakone. We are going to Kyoto on July 3-7. While in Kyoto we plan to take a side trip to Nara and also Arashiyama. We will then travel back to Tokyo for one night. We will travel to Yokohama on July 8 to board a cruise.

I'm not sure if we should buy a 7 day pass or a 14 day pass, as we will only be using the pass for 11 days. Any suggestions would be appreciated.

Thank you,
Laura