hakone travel

I will be travelling in a large group of 11 adults and 2 small kids from mid Oct 2017. I plan to travel from Tokyo to Hakone and stay there for one night. Then from Hakone to Kyoto. But with such a big group and 2 small kids, I don't want to drag the luggage along when travelling around Hakone. So I am wondering what is the best way to travel? Just do a day trip from Tokyo to Hakone, then travel from Tokyo to Kyoto? Or where can I keep the luggage?
Also I will be using my JR pass, so how would I use it to travel to Hakone because I heard that you can only use part of the JR pass to travel to Hakone.
Thanks for the advices.

You can only use the Pass to get to Odawara, then you would need a Hakone free Pass to cover your travels within Hakone.

Whether you day trip it or spend the night is up to you. Both options have their pros and cons.

You can quite easily to the "round course" trip with return from/to Tokyo. But you will miss out on some more relaxing features like baths/onsens.

Or you stay one night, deal with getting your luggage to your hotel first, then enjoy the "round course" still, but have probably 4-6 hours more time to enjoy some baths/onsens.

While not such a large group, I went to Hakone as a parent with a small child (and no other adults to help with luggage/said child so that ought to count for something...)

Assuming you are staying in hotels in Tokyo and Kyoto, takyuubin your biggest suitcases from Tokyo to Kyoto and just bring an overnight bag to Hakone. If said overnight bag is even more than you want to deal with, as long as you arrive in Hakone-Yumoto Station before 1 (it might be noon, you will need to check this!) you can same day takyuubin your bags from Hakone-Yumoto to most hotels and ryokan in the Hakone area. I did this with my small overnight bag because I was lazy and it was raining.

If you're staying at Airbnbs, if someone in your group knows Japanese you can have Kuroneko/Yamato Transport come to your unit and pick up your suitcases and set up an arrival time as well. If no one in your group can do that in Japanese, you might still be able to visit a Kuroneko/Yamato Transport office and just pick a time when you know someone will be in the unit for delivery. There are web guides for filling out the forms. I once needed to get a suitcase to KIX and it was past the time for suitcases to be takyuubinned from hotels, but I walked to a nearby service center, and was able to send my bag from there and I can not read Japanese.

These services do all cost money, but aren't ridiculously expensive and can be very worth it.