Travels with teenagers

If you decide on the Cinque Terre, shift your 3 nights from Sorrento and make that your seaside destination. You don't have enough nights to do both well. You can easily see Pisa in a 1/2 day on the way between Florence and the Cinque Terre and Verona as a daytrip from Venice. Long story short, don't add any more places to lay your head. 4 locations is a nice pace in two weeks.

I like #1s advise--I would do one or the other regarding CT and AC. Three nights is barely adequate for AC, and just doing CT as a day trip often results in misery (only by staying the night can you enjoy it without the crowds). Both offer hiking, if that is the draw.

Laurel's right, four locations is plenty, changing cities is not the fun part of travel. Siena is not a good base as the access to and from is quite time consuming. Stay in Levanto for the Cinque Terre and you could get parking for a rental car and more to do for the teens. Driving from Florence to Levanto you could visit Pisa (or Lucca for a bike ride on top of the best walls in Italy). From Levanto, you can see the five villages and Portovenere as well as make a side trip to Rapallo for the tramway to Monte Allegro and a ferry ride to Portofino and San Fruttuoso.

A ditto to all of the above.

If you want to do the CT, then substitute that for Sorrento as it's one of those places you really need to stay to make the most of the lighter-crowd hours. If you do it as a day trip, you'll be there when the crowds are heaviest and spend a total of 4 hours or more or so dealing with transport just getting there and back. Save Sorrento/Amalfi for another trip as you really don't have enough time for it, and it will involve backtracking any way you work it.

Long as we're talking transport, TRAINS are the best way into/out of and around the CT, aside from an occasional ferry ride. You do not need a driver as the villages are virtually pedestrianized.

I'll also agree with making Florence your base as it'll be much more convenient than Siena.

2 weeks: 4 locations. Keep in mind that you'll lose 1/2 a day or more every time you make a move, and a lot of moving around eats sightseeing time! You'll also need to spend your last night nearest your airport of departure so keep that in mind when making your itinerary? Into Venice and out of Rome is probably your best arrangement for this trip. Also do your homework on driving in Italy? It's a different animal than driving the States (if that's where you live), especially the restricted areas (ZTLs) where you cannot take the rental car. :O)

For the time you have and where the rest of your trip is, Sorrento is too far out of the way to make it a reasonable choice.

Spend that time IN Cinque Terre, not 'day tripping' to there

We went with our two teen agers last summer. I would keep Sorrento--it was one of their very favorite spots--and take two nights off of Florence and put two nights in Cinque Terre (another of their favorite spots.) For my teens, Florence was a LOT of moderately interesting sight seeing of churches and museums. They had enough after two days. But Cinque Terre they loved because of the beaches, the laid back vibe, the hiking, etc. I guess these are the same reasons they loved Sorrento except Sorrento was fancier and livelier--lots more to do. You could stop in Verona on your way out of Venice to CT. And you can stop by Pisa on your way out of CT. I would say the Lake region (assuming you mean up by Cuomo?) would be too much for your short time.

Have a great trip!!

Florence was a LOT of moderately interesting sight seeing of churches
and museums. They had enough after two days. But Cinque Terre they
loved because of the beaches, the laid back vibe, the hiking, etc. I
guess these are the same reasons they loved Sorrento

I don't know as we're recommending spending all of their 3.5 days JUST in Florence (although we've spent longer and could have stayed longer yet) but also using it as a base for an easy day trip or two, especially as the OP expressed a desire for Siena.

LOL, I'm chuckling a little over the CT having a "laid-back" vibe? Not how I'd personally describe it - or Sorrento/Amalfi Coast for that matter - during high season, which is when I'm guessing OP and family will be traveling. I also don't remember either having much for beaches outside of Monterosso and Positano. Anyway, I guess I'd look at this as Mom and Dad's trip too, and I don't know how much time they'd want to hang out at the beach or even hike versus allot more of that to exploration of interesting locations nearer a base?

I like the idea of a family bike ride around the old walls of Lucca: something active that would probably appeal to the teens plus provide sightseeing for the parents.

Kathy sorry you took my reply as a critique of your suggestion(s). Was not my intent. What was my intent was to give OP our family's perspective of our trip from July last summer. For sure my kids (and myself) really felt a laid-back vibe in both CT and Sorrento (this was my second time to CT and first to Sorrento.) And, while I love Florence, our teenagers (and our friends' teenagers) were done with Florence after two days. Hopefully OP takes it for my original intent, which was our perspective from visiting Italy in the height of tourist season. Traveling with teens is much different than traveling with young kids or with out kids at all. This was my 5th time to Italy and it was interesting to see it from the kids point of view.

Kathy sorry you took my reply as a critique of your suggestion(s).

No, no!!! I didn't take it that way at all!! More like just thinking out loud.
Multiple/different perspectives are a GOOD thing - that's what forums are all about - so it's GREAT that you added yours. :O)