My head is spinning with all the info surrounding the Firenze card. I'll be traveling with a 15 year old and a 17 year old. We're only in Florence for two days but are pretty efficient sightseers. I'd rather not spend precious time in long lines. If I buy one Firenze card, will my children be able to skip the lines as well? I understand that the sights are free for those who aren't yet 18. But will my children need to carry their passports with them to "prove" their age? I'm willing to pay a bit more for the card (then i'd pay purchasing individual tickets) if it'll be a big time saver.