Designing a park engages students in multiple roles. They have to decide on the best place for a park, learn about the population that will be frequenting the park and connect with influencers and city officials who can help make it happen, determine what are the best activities that visitors will enjoy, learn about local plants that would be best fit for the park and the types of facilities and park furniture that would be best for the park. By the end of the process, students can submit a well thought out park design to city officials, who may actually make it happen.
This is a long project, it could last a month or more, plan accordingly. However, students can feel really engaged in it because they will be directly involved in planning a real project that can impact their neighborhood.