Went there on Sunday.
Entry is $20 for an adult, however you can buy a year's adult pass for $60. Free activities include boating, golf (par 3 course), canoeing, archery, waterslides and, bouncy castles, and there are extra "pay for" activities that include go-karting and wall climbing (with safety ropes).
There's something here for all ages, and it'd be an easy place to take little'uns. Make sure you take towels and swimwear as they will get very wet.
Journey takes about 50 minutes from Hallett Cove down the A13. Follow the signposts.
Enjoy.
Kids will really love Greenhills we took our daughter and grandson there a few yrs ago when they were over here, couldn`t get either one of them off the water slide, we had a fab day, take a picnic with you, a fair bit of food as they use lots of energy, but Im sure you will all enjoy it
Sheila