Italy, Spring Break and 3 almost-teen boys....

I cannot recommend enough that you look at the video series done by PBS called "Traveling With Kids." They have done a number of episodes in Italy. You can view the episodes on PBS from their website, on YouTube, or on iTunes. I think it will give you some great ideas.

There were 2 YA book series students in my junior high liked. If your boys like to read, these books could whet their appetites and help them experience life in another time and culture vicariously.

The Roman Mysteries series by Caroline Lawrence (younger teens)
The SPQR series by John Maddox Roberts (older teens)

The weather should be fine and the crowds will definitely be smaller than during the summer. With regard to activities, as you get deeper into your research be sure to give consideration to their ideas about what they would like to do and see. No matter how close you are to your kids, they will look at things differently and have different desires about what they want to get from the trip. On of the things often overlooked in Rome is a day trip to Ostia Antica. Close by, inexpensive, can be gotten to on public transit, and totally different than Rome itself. As you plan, feel free to ask for specific info -- lots of folks here willing to help.

In Florence in the evening (8pm) go to TEATRO DEL SALE.
It will be about fun, music and florentine food.
I am sure they will love it.

And you must organise some day trips, if only for the experience of buying tickets and finding your train. Orvieto is a wonderful destination for a day trip from Rome; and from Florence a visit to Pisa is unavoidable with Lucca a good stop in between.

The Hotel Balestri in Florence is right on the Arno River and a great place to stay.

Easter can be very busy at the Vatican, but you will be in Florence then. The weather will be nice in April, perhaps a little chilly in the morning.

Rome and Florence are wonderful, lots of history, art, great food, etc.

We went with our 13 year olds and had beautiful weather in the high 50s-mid60s, sunny. Beautiful touring weather. I kept expecting rain, but we had none.
A few ideas about things to do in Rome with kids:

1. Go to TripAdvisor, type in "Le Domas Romane di Palazzo Valentini". It is ranked #16 of things to do in Rome with an average 5 star review. I recommend it to everyone, especially families with 5th graders and older---the earlier in your trip the better so that other sites can be more easily "imagined". The site is a reproduction of the interior of a Roman villa. It is the best educational multi-media presentation that I have seen anywhere. It doesn't beat Disneyland but it uses a variety of mediums to help you visualize/imagine what it was like to live in Ancient Rome. It is a terrific attraction for adults and kids, as long as you do not have mobility problems. Really spectacular visuals, sound effects, and narration. Read the reviews on TripAdvisor; they are 100% excellent . My kids loved it and so did I. Make sure you make reservations well in advance for the English tours. It is a bit tricky to find, tucked away in an alley, so allow extra time to locate it as your tour starts at a precise time.

2. I also recommend Ostia Antica, which Rick Steves covers well in his book and videos. Don't be daunted by its location. Very easy to take a train 20 minutes from the Pyramid metro stop, get off, walk 1/2 mile on flat sidewalks, and you are there. My children LOVED these open air ruins (Rick has a free audioguide). There were some school trips there but it is a huge area so not crowded. They were able to climb on things, run around, play hide & seek without bothering anyone. After all the inside time, it was good for them to get outside. (Note: There is no shade, bring hats/water/sunscreen; can get hot even in April. There are restrooms and small cafeteria serving...cafeteria food. Many recommend the restaurants between Ost Antica and the train station; we were not that adventurous).

3. Largo Argentina is a centrally located plaza and a historic area of Rome where Julius Caesar is said to have been assassinated. It is protected by a charming wrought iron fence but many people--young and old---visit the area for a quick peek of the historic site. The real attraction for my children (and young and old alike) was watching the many cats and their antics-- climbing up on the rocks and ruins (The cats did the climbing not my children!). Very entertaining, and again something outside.

4. Close to Largo Argentina Close to Pantheon which my kids also enjoyed for its tremendous sense of space...and intrigued by the idea of the "hole" in the ceiling. (another RS audioguide, a good one for kids).

5. If you haven't seen the website "Ron in Rome", take a look it had a lot of useful info for touring Rome affordably with lots of info about basic logistics (how to use the bus, where to go, etc).

The tourist area in Rome is very compact and kids are good walkers...especially with the thought of a gelato shop.
Feel free to private message me---have fun!