Family itinerary in July

Hi All, I'm looking for some advice with planning my family's first trip to Japan this coming July. I will be travelling with my husband and our 3 sons, who are 14, 12 and 10 years old and really good travellers. So far, I have organised the following:

Day 1 - June 27 - arrive Narita 9.05am. Travel to Shinjuku, Tokyo.
Day 2 - 5 - Tokyo (accommodation booked). Explore Tokyo & side trip/s
Day 5 - July 1 - travel Tokyo to Kyoto
Day 6- 9 - Kyoto (accommodation booked). Explore Kyoto & side trip/s
Day 9 - July 5 - travel Kyoto to ??
Day 9 - 14 - ???????
Day 14 - July 10 - travel ?? to Izu Imaihama (Kawazu area) - (accommodation booked)
Day 14 - 17 - relax at Izu Imaihama!
Day 17 - July 13 - travel Izu Imaihama to Nagoya
Day 18 - July 14 - Nagoya, attend Sumo tournament. Travel Nagoya to Airport Rest House, Narita.
Day 19 - Depart Narita @ 12.15pm.

Given that it will be summer, we don't really want to be running around trying to see everything in one trip!
I'm most interested in what recommendations people have for days 9 - 14 of our trip....we are keen to get to Hiroshima and Miyajima, but we are very open to all suggestions! Would like to do things that will interest the kids (samurai, ninjas are of interest to them!) as well as us. Fuji-Q Highlands is also of interest. (We have been to loads of Disneylands/Worlds and Universal Studios theme parks, so don't need to go to them in Japan).
We aren't planning to rent a car for any of this...would prefer to be able to get around using trains, buses etc., but would appreciate advice about this too, especially JR pass recommendations.
Any advice gratefully received! Thanks!

(1)Here are my suggestions for Days 9 – 14.
Day 9 Leave Kyoto in the afternoon for Hiroshima; overnight in Hiroshima
Day 10 Full day sightseeing in Hiroshima
Day 11 Excursion to Miyajima (JR PASS is good for Miyajima Ferry also)
Day 12 Leave Hiroshima for Okayama then enjoy the half day city sightseeing; overnight in Okayama
http://www.japan-guide.com/e/e5700.html
Day 13 Excursion to Kurashiki
http://www.japan-guide.com/e/e5750.html
Day 14 From Okayama to Izu Imaihama

Please make sure that your Shinkansen train stops at Atami on Day14, as some of them do not stop at Atami. That�fs where you transfer to the train to Izu area. If you are catching Kodama train which runs mostly from Osaka, you might enjoy the sightseeing in Osaka using your JR Pass, on the way to Atami. Nagoya is a better choice if you think about the time to ride the train, but you are visiting Nagoya later anyway.

(2)Here is the information on Japan Rail Pass.
http://www.japan-guide.com/e/e2361.html

(3)Fuji-Q Highlands
Why don�ft you go there while you are in Shinjuku? The access is very good from Shinjuku to Highland station via Otsuki. This is the end of Part 1/2.

Here is the Part 2/2.
(4)Ninja
http://www.japan-guide.com/search/?cx=015609760794546757367%3A7rvvvope...
I have not been to this kind of places, but judging from what people say on website and considering the ages of your sons, you would probably like to take them to Iga Ninja Museum or the Koka Ninja Village while you are in Kyoto. They are both within one-day trip distance from Kyoto.

(5)It would be better if you watch Sumo right after you travel from Izu on July 13. If you leave Imaihama Kaigan station at 8:34, you get to change trains only once at Atami and arrive at Nagoya around noon. The best part of Sumo, with better and best Sumo wrestlers�f matches, starts around 4:00p.m. and ends 6:00 p.m.

Just in case there is some delay in transportation, it would be better if you leave Nagoya in the morning July 14. After arriving in Narita, your kids might enjoy the Museum of Aeronautical Sciences near Narita Airport Resthouse. It is one stop from the train station right in front of the hotel (this is private train company; JR pass is not accepted, though).

Thankyou so much yagi! Great suggestions. I will see if I can change my sumo pre-order to 13th July rather than 14th July. I really appreciate your help with this....