Homework and Incentives

I have had a hard time getting students to care about the effort they put into their work. I noticed that homework completion started to become a problem as soon as the points were taken away from it. I've been told that giving points for homework is not the "correct" thing to do. As homework is supposed to be used as practice and how can you grade practice? I have read about grading and what is the "right" way to do it. Grading should be more standards based and not inflated by extra points (such as giving points for homework assignments). I am hoping to tweek my grading system and start the year (2011-2012 school year) with grading only by standards. However, this year I have been changing my mind left and right as to what is the correct way. I have not given points for homework at all this year and now I feel obligated to start for quarter 4. The reason I want to start giving points is because I have noticed almost a direct correlation between homework completion and the percent of students who are earning a grade of D (65%) or lower. One of my classes had 91% homework completion, and a failure rate of 9%. Another class had a homework completion of 47% and a failure rate of 49%. After speaking with many students, they have mentioned that it is hard to feel obligated to do the homework if it is not giving them points. So, instead of giving points during quarter 3, I created an incentive for all of my classes. The class with the highest homework completion was to be rewarded. (I brought in suckers that they were able to have on the last day of quarter 3). The students were excited and proud that they were the "winning" class. It has almost started a competition between all of my algebra classes. I am looking forward to quarter 4 in order to see if this drive continues.