Stay near the airport, head out in the morning. Depending on how much time you have- On the way I would consider a stop at Sandy Hook (though it’s a little out of the way), beach towns along the way like Asbury Park and Ocean Grove, Point Pleasant has a small aquarium and boardwalk, then further south Wildwood for a classic NJ boardwalk, and Cape May Zoo is a fun day with kids. There’s no way to do all of that in a day but it will give you some ideas to look into. It will be a shorter drive if you fly into Philadelphia, but that’s a whole different drive.