Landal

If you have little ones and are looking for something  phenomenal to do indoors, and gets your kids energy out- then Landal is the place to go.

Landal is a resort area that has cabins, camping, restaurants, pools (indoor and outdoor), etc.  BUT, if you just want a 45 minute drive to do something fun for the day or half a day, Landal is a great choice.

...and its FREE FOR ALL MILITARY AND THEIR DEPENDENTS!
Yes, folks-FREE.  Just show your military ID before entering into the play area.
(update Dec. 2016-they now charge a small fee, even with your military ID.  It is 3 euro per child)

This place is really great!  they have a padded play area on the floor that is enclosed by these soft wall blocks for crawlers and babies (you can see it in the bottom of the above picture).
But the great part is the castle like play area.  I have a 6 and 4 year old and they are both able to do all of it. I've even worked up a sweat playing and climbing with my kiddos myself. It's big enough for adults to go in and have a little fun with their kiddos.
They have air hockey and some other games that cost 1-2 euro, but the actual play equipment is free.  there is a trampoline that you can pay for too...it's around 2 euro for 3 minutes or so.
This play area is  massive and so much fun!

    

There is a little snack shack and really nice seating area for the adults to sit and what I like about it (confession of an overprotective mom) is that from almost anywhere in the seating area you can sip a cappuccino and see your kids almost anywhere they are in the entire play area.  It's clean and nicely open and cutely decorated.  (and the bathrooms are clean and FREE)

My kids and I ate lunch there and it cost about 30 euro...but was really nice.  You cannot bring your own food in, so be prepared to buy something to munch on.
When you drive there it feels like you are not supposed to be there at all...you drive though a resort area and through narrow, curvy roads.  Once at the top, after driving through some of the resort (passing the outdoor water park area) you will find a really nice restaurant...in the back of that restaurant is where you'll find the play area.  I know that sounds crazy, but the back of the restaurant opens up to this huge play area.
Outside the restaurant is a trampoline like 'bubble' on the ground for kids to jump on and a little wooden water splash zone (only operational in the summer-it's just enough for the kids to splash their hands around in and have fun with a bucket and little wooden water bridges and such)

Here is the link:  Landal

If you are at spangdahlem, the playground that is featured is the one in Sonnenberg (it's the closest).  The address is:

Landal Sonneberg 
Sonneberg 1 
54340 Leiwen 
Mosel 
Tel: +49 (0) 6507-936 90 
Email  sonnenberg@landal.de  

GPS coordinates

49 ° 48 '12.5'' N 
6 ° 53 '30.4'' E

Monday to Friday 9:00 - 21.00 clock 
Saturday, Sunday and holidays 10:00 - 15.00 clock

Phone #:  01806 - 700 730