We really think its great you're reaching out for some help to motivate your 9 year old to follow through on things. Some activities we believe you have in mind include completing chores, following directions, and being successful in his or her daily routine. None of these are things that would be unreasonable of you to expect of your 9-year old, so we think its great your reaching out for some help with this!
The following article provides a great process for a child to follow when given an instruction. Check it out and see if it is something you could apply with your child. Take special note of the last step of checking back in with the person who gave him or her an instruction- this helps them stay accountable by being expected to check in with the instructor once the instruction has been complete. Like we said, here is that article: http://www.parenting.org/article/following-instructions
Here is a website that I found to help you to better understand your child. I hope this helps you as much as it helped me. It contains some important information about how the child is always motivated it goes on and explain that our children likes to resist us because they like to do things their way, not ours, this helps them to continue to have power.
It explains that when children feel powerless, they try to feel powerful by withholding. A child who feels very powerless will stay in bed, not go to school, avoid homework, sit on the couch and continue to withhold overall involvement because it gives them a sense of being in control. To the parent, the behavior looks completely out of control. But the child sees it as the only way to have power over what’s going on around him.