Amusement park in the Taunus, North of Frankfurt. As a parent, I give the Lochmühle top marks. It's…read moreclean, well maintained, and offers parents the opportunity to just chill out while the kids run wild. For groups, there are Grill huts in varying sizes (need to reserve ahead of time). The larger ones can accomodate 25-30 people and the beauty is, you can bring all of your own food and drinks and you don't have to schlepp it around the park in a rucksack.
The rides are pretty much for kids age 2-12. Older than that and they'll probably lose interest. Older kids would probably prefer the Taunus Wunderland (see other review). There are also a number of animals including a petting zoo.
Even if you don't reserve a grill hut you can pack a picnic blanket and park it next to the small stream or in other grassy areas and just chill out.
Prices are very reasonable from my perspective, both for admission and for food prices. This park is not out to gouge you. That being said, the attractions are NOTHING compared to a U.S. style amusement parkthis is, after all, kidstuff.