Day trips out of Garmisch using Bayern Pass

I can't really add much, as you have already listed some good options. Innsbruck, although not my favorite city, has a pretty lively Weinachtsmarkt (Christmas market). Linderhof is likely open, but don't expect too much from the gardens. It's probably obvious, but if anyone in your party is a skier or boarder (or would like to learn), you will be staying in one of the ski meccas of Europe.

Innsbruck is not accessible with the Bayern Ticket. But from Garmisch you CAN head into Tyrolean Austria on the "Ausserfernbahn" route with the Bayern Ticket. You'll pass through some great scenery and among others the Austrian towns of Vils (near Füssen) Pinswang (where a short trail heads through the mountains to Ludwig's castles) and Reutte; if you stay on, you end up back in Germany in Kempten, the end of the line. In Kempten, other lines head south to Oberstdorf and north to Memmingen and Ulm. http://www.ausserfern-direct.at/images/ausserfern-rail.gif

Are all six of you traveling together? If so, you had better confirm at the Garmisch Bahnhof that you all can indeed use one Bayern-Ticket. The Bayern-Ticket, as I read it, is for a group of up to five people OR a parent or parents and all their own children under 15. I don't think it means a group of adults with all the children of one adult. On the other hand, children 5 years and under are free. Maybe you could use a Bayern-Ticket to cover the four adults and the 8 yo, then buy a "ticket" for the 5 yo, which is free? Best to ask. Also, a lot of the destinations Fuessen, Oberammergau, Linderhof, Mittenwald) can be reached by buses of the RVO (Regionalverkehr Oberbayern). RVO accepts the Bayern-Ticket and a day pass (Tagesticket) for a child is only €5,50 more. ETO: I just found the answer on the German language side of the Bahn website under "conditions" for the Länder tickets, "Kinder bis einschließlich 5 Jahre werden ohne Fahrkarte unentgeltlich befördert. Bei der Ermittlung der Teilnehmerzahl werden sie nicht berücksichtigt." "Children up to including 5 years are transported free of charge without a ticket. They are not included in the count of participants." So, you can use one Bayern-Ticket for all of you.

You can use the RVO bus(es) to go from Garmisch-Partenkirchen to Fuessen (via Oberammergau). But mind the time, the last bus back from Hohenschwangau (by the castles) leaves there at 17.23 (5:23 PM). Don't get stuck in Fuessen. There is a bus from the bus stop at Oberammergau to Linderhof (about 25 min). If you get off the Ausserfernbahn in Reutte (or Vils) the bus to Fuessen (at least the Austrian part) will not be covered by the Bayern-Ticket, but if you get off in Pfronten, the bus to Fuessen will be covered.

As for getting to Innsbruck, Austrian Rail has a pass like the Bayern-Ticket. It's called the Einfach Raus ticket and sells for €28 and is valid for travel by regional trains all over Austria by 2-5 people. I haven't looked at the Austrian Rail website yet to see how they might handle the 5 yo, nor do I know how you might purchase it. So you might be able to use the Bayern-Ticket to the border and the Einfach Raus ticket from there. I don't know if the automat in Garmisch or Mittenwald sells it, or if you can buy it on the train. It's probably for sale at the station in Seefeld, but you might have to pay to get there. Up_date: The Einfach Raus ticket can be purchased online from Austrian Rail. They ask for an email address but not for a mail address, so presumeably it sent electronically for you to print at home. I found this on the Austrian Rail website, "Kinder bis einschließlich 5 Jahren reisen generell kostenlos und benötigen keine Fahrkarte." Children up to including 5 year travel generally free and don't need a ticket.

I would add Hohenschwangau while you're at Neuschwanstein. You can get a combo pass. Hohenschwangau is very overlooked. Also, they just opened a Museum about the Wittelsbach's in Schwangau that contains items and family history which may give some interesting background to the folks that built those castles. Also, Innsbruck, although not reachable with the Bayern pass, is well worth the trip. The Hapsburg Palace is there, the worlds largest Swarovski store with a changing display in the basement, as well as the Golden roof, the sacher torte store and several other fun things to do. Granted some tend to be touristy, but sometimes you have to bow your head and enjoy the inevitable.
Also, the kids may enjoy a ride on the cog wheel train called Achenseebahn, that is near Innsbruck. I know my Husband and I and a friend had a grand time and the views of it are breathtaking. Located at Bahnhofstraße 1, 6200 Jenbach, Austria Here's the website: http://www.achenseebahn.at/ If you take the first train of the day, there is a discount on price and you can combine it with a cruise around the achensee.