Helping my son procrastinate less

The best thing you can do is teach by example. Show him the benefits of not procrastinating and it's more than likely he'll catch on.

Create a structured work plan for immediate goals.

Divide each task to simpler smaller tasks and help him decide to accomplish these on time. 

It sounds like although your son procrastinates, the end results are more positive than negative.  I would attempt to help him see that by not procrastinating his end results would lean more to the positive side.  Also, if procrastinating is interfering with his academics and/or sports, putting more effort into it earlier on will have the greatest impact. Teachers and coaches will notice! This comes from a 40 year old mom of two boys and two girls, my sons are in college, one of which is graduating in May.  Both had some issues of procrastinating and they both came to the conclusion that eventhough mom rides their backs about studying or looking over notes the day they were given and researching earlier for a project tends to not have as much stress behind it and that's when they were the most proud about what they had accomplished.  I think that being there for your son is also one of the most important ingredients you can do for your son too.