I’ve recently been informed that the massive Lido Playground (next to the Verkehrshaus) is open for free in the winter. If you haven’t been there, it is huge and fun for kids of all ages.
Thanks Dolly for your recommendation:
I took my son there and it was lots of fun! It is a really big park with lots of swings, forts, slides and other things for kids to play on. After we had been there about 30 minutes, several other families showed up but it wasn’t crowded at all as there were plenty of fun things for all of the families to do and kids to play on.
There is also Put Put Golf across the street for families not to mention three different museums all in one place!
More information can be found here: www.lido-luzern.ch/spielplatz.php (written in German)