Sounds challenging....but I just found a great resource to help in planning guidelines and checklists for projects at a site called Project Based Learning. Check it out!
￼From this site, educators can use the checklist tool to generate guidelines for projects in writing, science, oral presentation, or multimedia. Naturally, I lean toward the multimedia, and I encourage you to explore here as well. Starting with the checklist can aid tremendously in the planning of the overall project, and it will certainly help you clarify your expectations. A word of explanation from the site:
Completing class projects can be fun for your students, especially if they know exactly what is needed. Creating guidelines can be time-consuming though, so we've made a way for you to do it in no time! To make a project checklist for your students, first choose the grade level for the type of project you want your students to do. You can choose from writing, presentation, multimedia, or science projects. On the next page, choose from our list of project guidelines, and make a checklist with the touch of a button! You can even add your own criteria to personalize your checklist.
Also from the site you will find a link to Rubistar, a resource for creating full-fledged scoring rubrics for your projects. You must register for an account, which is free, to be able to work on and save your rubrics online. This way you can work on them from home or school. In addition there are helpful “starter” templates you can edit and mold to suit your individual needs.