Is this too much in 3 weeks with 2 tweens or could we do more?

I think it matters what you want to see? For me, 3 full days in Venice was not enough, nor was 3.5 days in Florence. But I like to wander, sit and people-watch, really experience things. If you want to power-sightsee and check the museums off a list, your plan is probably ok. But in cities like Venice and Florence, where these places' best assets are, IMO, the cities themselves and their character, being there for that short a time does the cities, and your family, a disservice. I'd say definitely forget Rome, I was there for 4.5 days and didn't see nearly as much as I wanted to. I did 10 cities in 45 days - 4-5 days in each city, and this felt like a really fast-paced trip and beforehand people told me to cut stuff out. I didn't and I'm glad, but I still did leave myself several days in each city to relax and just experience each place. If you want to be running around, then keep what you have. But if you want to really experience, think about cutting down. Only you can decide!

Margaret, sounds like you have a great trip planned and one that your tweens are going to remember for a lifetime. Here are a few things to consider:
Pisa is a decent day trip from the CT, but about the only thing to see there is the tower, etc. You'll spend a lot of time traveling vs. seeing. Pisa is very efficiently done as a stopover en route to somewhere else.
Florence and Siena are not conducive for day trips from the CT. There's just way too much to see in both places and they are not efficiently close to the CT. You will spend a very large chunk of those 4.5 days en route to/from places.
Most people who have traveled with kids under the age of 16-18 (including Rick Steves) recommend no more than one major sight in a day. So if you're hoping to see David, the Ufizzi and other major sights in Florence then you will need as many days as sights.
IMO I never plan for more than 25% day trips. If I do more than that I feel like I'm spending too much time going from pt. A to pt. B.

My concern is north of Jarrod's. Rothenburg is 4 hours north of Munich; that means 8 hours for a day trip. It's a wonderful town, but that is all it is so it might not be as cool for your girls. I think Neuschwanstein and Salzburg (both 1.5-2 hours) are great and then there is plenty in the Munich area.

With regards to Linda's concern about the 4 hour trip each way to Rothenburg. We are wondering if there are nice worthwhile places to stop along the way from Munich to Rothenburg that will make a trip there more worthwhile than just a simple one town stop in Rothenburg. We'll likely be driving.

Margaret, there are some fantastic places to stop between Munich and Rothenburg. If you can manage to stay along the Romantic Road then that, in itself, if a great "sight". Also, stop in the towns of Nordlingen and Dinkelsbuhl which are along the Romantic Road.

The other potential place to visit between Munich and Rothenburg is to drive through and stop in Nuremburg (Nurnberg, whatever). It's a larger city with big city type things to see. The Deutsche Bahn museum is there, and that's something different to see. Also there are some great Nazi and WWII sights. It would be a nice change of pace from the rest of your trip.

Again, though, only one major sight per day. Otherwise you'll just have cranky kids on your hand. I don't know your kids. You're a better judge than I am.

Just remember one significant piece of advice that Rick Steves or anyone who follows his advice also follows. Plan your trip like you're going back. You can't see everything. There's WAY too much.

Yes, skip Rome. Too much.
I would not spend 6 days in Munich either.

I think you are doing too much, but, you know your kids.
I went to France for more then 2 months when I was 13, I remember complaining " no I don't want to go into Paris( my grandmothers house was 20 minutes outside of Paris) today, can't we just stay home" because my relatives planned lots of sightseeing for me, including trips to Normandy, Brittany, and Dordgone regions,, I just wanted some down time. That was within a 70-80 day trip,, your 21 days looks pretty rich to me.
Have you talked to your kids about what THEY want to see?
When I took my 14 yr son two years ago I MADE him do some research and contribute to trip planning and had him choose three things he wanted to see. I think kids get more out of a trip they contribute to planning, not just get " taken" on. Your kids are definately old enough to look at a guide book or computer site.
My son discovered the Catacombs in Paris,yuck, LOL !

Hi Margaret, I agree with Jarrod's first reply. In a 21 day trip in those countries, you need to be in Florence for three nights. That would give you two whole days : one day in Florence, and a day trip to Sienna. Why do you want to drive ? Trains go to all those places. (Bus to Sienna from Florence). You will not have time to go to Rome. I am not enthused about Rothenburg : if you insist on going there, stay there one night. Instead of using two days to go to Rothenburg, I suggest plan for more time at the Alps in Austria or Switzerland.

Margaret, just get yourself a fantastic map of the area and a great navigator. The Michelin maps are top notch and my wife tends to be a great navigator. Driving means that you'll have to make sure you get nearly turn-by-turn directions of everywhere you want to go before you leave. http://www.viamichelin.com is the best site for getting directions in Europe. Do more research about where you are planning to drive than you have ever done in your life. You'll be glad you did.

Margaet, I can tell you exactly why you want to drive beyond flexibility. On the Deutsche Bahn website, travel for 2 adults and 2 tweens will be a minimum of 64 EUR per person or about $90 from Munich to Rothenburg o.d.T. That's $360 just for one segment of the trip. You can rent a car that will fit 4 people plus their luggage for an entire week for that price. Then all you will have to pay for is gas and the occasional parking stall.

Buying a railpass may save you some money. Check out the Eurail pass Germany are of this website: http://www.ricksteves.com/rail/germany.cfm. My guess is that it's not going to save you nearly as much money as renting a car. In this day and age of a deplorably weak US dollar and a very robust Euro, you need to save anywhere you can.

We did a simelar trip when our kids were this age(about 10 years ago) We hit Paris, Murren(Switzerland), Salzberg, Venice, Cinque-terre, Nice & back to Paris in 4 weeks. We took the train the whole trip & I would definately recoment that. You don't realize how much driving is involved until you are all stuck in the car all day. Most of your sites are on the train route & it allows you to interact & sightsee while you travel (and go to the bathroom). The train stations are such an important part of seeing Europe, and Rick has great hotel recomendations near the station. We actually did our trip with no reservations & no definate idea where our next stop was. It was great & we had no trouble. This is even easier today with cell phones & Rick's book to call ahead & book a room in the city you're going to.

Yes, we want to drive because of the cost. I feel that the rail, while a good option, will push our costs up tremendously. Even Rick Steves recommends to drive when you have a family of four. I guess that's the way he travelled with his kids when they were younger. I think we can still take advantage of the driving. There's a lot of small towns we can see that we probably wouldn't if we are on a train. Thanks everyone for your input.
Margaret