Yes, requiring participation in discussion threads is a great way to get students involved. Thanks for your comments!
Yes, this is a concern for the adult student since they generally have busy lives. Having students participate in Threaded Discussions is very important. They can be involved as time permits for them. In the classes I teach, students receive a grade for their involvement. If they respond to the question, they receive points. If they respond to other classmates' comments, they earn additional points. This method encourages each student to stay involved.
Beth, you make an excellent point regarding "the distraction factor from home. "As both and online instructor and an online student, I know that my time is at a premium and definitely affects my participation as a student. Some weeks, I participate only enough to earn my points, honestly.