ack! Venice, Florence, and Rome. What do I need to book in advance?

Book nothing if you are not sure. Maybe just the hotels if you are set on dates and locations. Otherwise improvise. I never book anything in advance except for the rental car (which you won't need if you just go to Venice, Florence, Rome) and some (but not always) hotels/accommodations. I often book the hotel the morning I decide to head that direction (or the day before, if I know I'm going to that location for sure). Just carry a device to get wifi access to the internet if you can (iPad, portable computer or smart phone). You can always findsome accommodations in those locations on the spot. They may not be exactly what Rick Steves recommends, but there are lots of other places available, even on the same day. I recommend these number of nights (minimum): Venice: minimum 2 nights Florence: minimum 2 nights (more if you plan day trips to Tuscany's smaller towns)
Rome: minimum 3 nights

In Florence, you already know about the Uffizi; there's also the Accademia, with Michelangelo's David (I actually preferred the Rape Of The Sabines, and as a bonus, I had it all to myself). In Rome, the Borghese Gallery requires reservations, and the numbers are strictly limited. If this interests you, get them now. If you want to see Giotto, you should try to get to his frescoes in Padova (they really are magnificent). Admission to these is by reserved time slot; I don't know how hard it is to get one on short notice. If you only have three days in each city, there will be PLENTY to see and do without reservations, so I think your plan is sound. Of course, you may miss something you hadn't reserved; but you will miss plenty under any circumstance, and particularly with an 11 year old in tow, spontaneity may be more important than any one sight. If you aren't traveling with Rick's books, here's his tips for Rome with kids: http://www.ricksteves.com/plan/destinations/italy/02kidsrome.htm

Thanks for the quick responses! a few clarifications: We have hotels booked already
We are in each city for 3 days Thanks!

mary, Are you travelling with a Laptop or iPad? You could perhaps download the Italy 2013 Guidebook, and with that you'd have good information at hand to plan touring "on the fly", according to what interests you the most. The book also provides lots of information on transportation, opening & closing times for various sights, etc. For visiting the Colosseum in Rome, one of the easiest methods is to buy a combo ticket on Palatine Hill, which covers the Colosseum, Palatine Hill and the Forum. There's usually less of a queue there. Don't be distracted by the hawkers selling tickets out front and asking "do you speak English". When you get inside the Colosseum, I'd highly recommend taking the "official" tour. As I recall, they provide Whisper Headsets so that everyone can hear the guide. One advantage of that method over using an Audioguide is that you can ask questions of the guide for more information. Depending on your budget and the tolerance of your 11-year old, you could also arrange a walking tour with a local Guide. Francesca Caruso is an outstanding guide in Rome, but at this time of year I suspect she's very busy. Happy travels!

In Venice, take a traghetto across the Grand Canal - it's short but you ride standing up in a gondola, costs about €1 each. I think the gondolas are way overpriced. The vaporetto rides are very scenic. If you can get reservations, you could easily stop in Padua on the way from Venice to Florence for a few hours. In Florence, often the Academia (where David lives) is not crowded late in the afternoon. You won't need much over an hour there, if that. If you love sculpture, go to the Bargello and the Duomo museum (which is in a separate building behind the Duomo). The Baptistry has a wonderful mosaic dome inside. In Rome, the Vatican Museums are extensive and often crowded. Since they are closed on Sundays and most other museums are closed on Mondays, Monday is the most crowded and to be avoided. If you reserve tickets in advance, you avoid the long line, which can easily be an hour. I'm not sure an 11-year old would really like the museums, though. Do go to St. Peter's. Earlier is always better, sometimes the security line gets pretty long. If you want to climb up the dome - for a great view - you should do that as soon as they open. The security line is the same for the dome and the church, you can visit either first. The church opens well before the dome. The dome has limited space, so the line gets long rather quickly. I think you can really wing it - whatever you don't see this time. . . .

I've been with children who really enjoyed exploring the roof of St Peters (and if you want to climb the dome, you start from the roof entrance). In Venice, he might enjoy Torcello. It's about an hour by vaporetto to get there, but it's largely deserted, with an early church with amazing mosaics. And vaporetto rides themselves can be really enjoyable. I like the view from the campanile of San Giorgio Maggiore better than San Marco (and it didn't have a line when I've visited a few times in the fall). With an interest in Giotto, definitely visit Scovegni chapel in Padua if you can; at this time of year, you should make reservations. It's an easy train ride from Venice, about 30 minutes. And you're only allowed a short stay in the chapel, so it shouldn't try a young person's patience.

Consider paying extra for the Vaporetto dell'Arte in Venice. It goes up and down the Grand Canal and functions as a tourist hop-on-hop-off bus, with audioguides. Although it takes the same route as the regular vaporetto #1, it's nowhere near as crowded. (The #1 can be so packed with people and luggage that the don't let more people on - think subway car in rush hour.) No need to make advance reservations Here's the url: http://www.vaporettoarte.com/index.php/en/what-it-offers

When in Rome, we purchase the Roma Pass. It also includes transportation. There is a list of sights you can visit using the Pass. Recommend that you visit the three most expensive sights. Does not include the Vatican. The Roma Pass will also allow you to skip the line. One place I wouldn't miss while in Rome is the Borghese Gallery. It is amazing. Reservations are mandatory. Roma Pass covers entrance. If you contact your hotel in Rome, they will make the reservation for you. I would do that immediately. Since you have an artistic background, you might not want to miss Michaelangelo's David at the Accademia. You will however need reservations. You might want to contact the hotel where you are staying in Florence to see if they will make reservations for you. We also enjoyed Piazalle Michaelangelo. Please keep in mind that this is the high season and all sights will have lines. August is generally the month when many Italians go on vacation. In the past, many restaurants in Rome are closed. However, I recently read an article that said due to Italy's economic problems, many Italians are foregoing their vacations and as a result the restaurants in Rome have remained open.