I'm lucky my 5th graders are a really good group, but 8th grade and 3rd grade are just like your 5th grade. Another strategy you could try is if your in the middle of a lesson, they are working independently try read to them. Pick a good short age appropriate novel I like Mary Downing Hahn. Try "Wait Till Helen Comes" it's a ghost story they will like it. Or if you don't like to read try an audiobook or a movie. Some projects need other distractions. I know I work best when I listen to my favorite audiobook or movie playing in the background.