From Lancaster you have a 30-45 min ride depending on where you are staying. IF you want to be there and at the gate before 10, parking and a long walk to the gate I would leave an hour before to be safe. They have bathrooms right before and right after the gate so the boys can get ready becasue the "good" coasters all have a line nif you are not one of the first ones.
Have a Great time and dont forget to pack your suits since they have a neat water area inside of the park. Also a small zoo to walk and cool off in when the heat gets too you (LOTS of hills to walk).
Also dont forget the seal/sealion (?)and dolphin show!HP Season Pass holders
I don't know when you were at HP last, but there hasn't been a dolphin show for at least a few years- only the sea lions now.
OP, if you want to beat the crowds, you need to get to the park by at least 9:15 or earlier. It will take you at least 15 mins to get in the park, pay for parking, find a parking spot and walk the mile to the front gate. Most people start lining up at 9:00am. Also, if you already have your tickets make sure you go to the far right turnstile- it is always the least busy.
From Lancaster, depending on what part of town you are staying in, it will take you a good 45 mins to get to Hershey. Traffic getting into the park can get very backed up, so figure on another 15 mins to get from Hersheypark Drive just to the entrance. There are only 2 ways in- a North entrance and a South entrance and they both form into 3 lanes.
Once you get into the park, you have two choices. Choice One, you go straight to the Boardwalk (waterpark) and skip everything else on the way. Once there, grab a few seats and plop down your stuff. You will want to do the Coastline Plunge rides first- they get the biggest lines. Second is the lazy river, and then the Rollar Soaker. After your fill of the waterpark, head out of the Boardwalk and make a left and do Fahrenheit, Sky Rush and Sotrm Runner first. Those are the 3 major rides with the longest lines. The Great Bear, Racers, Sidewinder, Wildcat and Comet have shorter lines. Do the coasters first and then the other minor rides.
Your second choice (and probably the best for the boys) would be to hit the major coasters first. You will have to decide which is more important to you- the SkyRush (Hollow) or Fahrenheit (in Midway America) and then get in line for one of those first thing. After hitting both of those, head to Stormrunner and then The SideWinder (right beside each other and both in Pioneer Frontier). Greatbear is in Minetown and is an easy walk from the Hollow.
We are season pass holders and live in Hershey and are at the park at least 3-5 times a week. We have our own way of touring depending on the crowds, so if you want a more detailed plan let me know and I can tell you what we do.
As others have said, HP is very hilly and requires alot of walking and backtracking to hit the major rides before the crowds get overwhelming. The best place for food is in Pioneer Frontier. We usually hit up Subway as it is the cheapest, but we also enjoy the Wurstburg Grill.
Best thing to do is look at the park map online first and highlight what is a must do and work around that. Try to get everything done in each section before you move on to save on walking. Parking is $12 for non season pass holders, so have your money ready when you pull up and it will speed up your entrance.