Weekly Coaster Challenges are longer and harder missions that will ask you to build a specific type of coaster and fulfill different goals. All the goals must be achieved to complete the Challenge. Challenges are a kind of puzzle, where you have to try different designs and be creative to fulfill all the Challenge requirements. Each week will bring a new Challenge that will adapt to your level.
A Coaster Challenge can ask you to have a coaster of a certain length, a maximum height, or place a specific Special insert or Train, etc. Any coaster stat can become a goal!
You can complete Challenges by editing the coaster you currently have in your park, or by building new ones. Once a coaster fulfills all goals you can claim your reward: Special Insert or Trains and Stations cards. The reward must be claimed before the timer expires or else you will lose it.
Consult the Mission Menu on the Challenge tab to see your current Challenge.