Upon arrival, we checked in to Hersheypark Camping Resort, formerly Highmeadow Campground or something along those lines. We had rented a couple 1 bedroom deluxe (= includes a bathroom with a shower) cabins, one for us and one for my sister's family. They arrived shortly before us. My husband's aunt, who is also the minister who married us, came by to see us the first evening. She brought dinner: vegetarian lasagna, turkey tenderloin, a giant salad, fruit on some kind of angel food like cake, beverages, etc. Wow. Thank you! The cabins were clean and well stocked. We went swimming, however, the (unheated?) pools were kinda cold still. The bunkroom in the cabin had three single beds and one double; we never used the queen sized sofabed in the living area, altho A. did sleep on a kid-sized AeroBed out there.
The following three days we went into Hersheypark. T. and R. went on coasters. All of them. Repeatedly. A. and I did a lot of kiddie rides, and also the less scary flume ride, Coal Cracker. We also rode on the gondola ride, Sky View. There is one (1) dark ride, which is like Santa's Village Humbug or Disney's Buzz Lightyear and similar: a pretty simple ride vehicle with a couple light guns that you try to hit targets with. The theming involves Xtreme sports, and there is a team competition element (Team Chocolate vs. Team Peanut Butter). It is incoherent but fun.
Sit-down dining is limited to non-existent, but counter service options are pretty broad and the food quality was decent. Pricing is about what I expect from an amusement park. Unlike Disney, there are several hills in the park.
One coaster, Trailblazer (which I actually remember from my previous trip in 2000), was down the whole time, which was sort of a bummer. Their new-this-year kiddie coaster, Cocoa Cruiser, is a 3x through tiny coaster.
My sister's family went to ZooAmerica on the third day. They liked it.
On the second and third day, A. and I spent time in the waterpark/Boardwalk at Sandcastle Cove. We enjoyed that.
One of the nicest things about HersheyPark is the sheer number of kiddie rides. While obviously this is fundamentally a coaster park, you'd never know that if you were spending your days with a wee one, because you won't really run out of little kid stuff to do. There are also a lot of trees, so it is possible to mostly stay in shade if you are careful.
Because it is conveniently located (within a couple hours drive) of many of our relatives (mine and R.'s), we will likely come back to HersheyPark within a couple years, and we expect there will be even more fun things to do then, as they consistently upgrade the park.
My sister cooked dinner two nights; I cooked one night. We had breakfasts in as well but mostly had lunch in the park. Stores, including a mall, and fast food are conveniently located nearby (about a mile or two away). R. forgot to pack swim trunks and was able to buy two pair at the nearby mall quite quickly for a very reasonable price.