If you are building a course on a budget or need free resources, the following are free, or inexpensive, resources to help you build your course. Most of these resources require a login and it might be helpful to have a Google or Facebook account to login to these resources.
Although Microsoft Office products are not free - there are many creative ideas one can develop using Powerpoint that goes beyond text and pictures on slides. PowerPoint offers a lot of solutions for building course modules.
Here are some resources on how to use the features of PowerPoint to build interactive modules: