Willfull 6 year old boy, on my last straw

I stand by the chart/contract. There IS something he cares about that will offer leverage, you have to find it and run with it. I would consider formal testing for ADHD and also maybe a phsyc eval and counseling. Negative breeds negative. He has learned that eventually adults give in, that wont undo itself in a short amount of time. The comment on the daily or weekly rewards says it all to me...."you can give it to me anyway" Well....yes we can but we wont until it's earned. One time giving in to a smart fella like this is a major set back. I wouldnt be using food as a punishment (in our area it's not allowed) if you need to with-hold desert then do it as a whole and not as punishment. Cut him off refined sugars and treats (if he gets them now) and try for natural stuff. He can refuse to go to bed early, but he can also go an extra 15 min early every night till he gets it right...did that with my boys when they were a little younger and it took a couple of days of going to bed directly after dinner and they "got" that I mean business and they stopped messing around! You may have tried some of the ideas you've been given, tweek them a bit, put it in writing, meet with the teachers and again, unless he has been formaly tested I would get that done. Talk to transportation and your CW about things that are ok to use as discipline...like having him walk regardless of weather while you drive behind him...it's chilly now, he may not like it and if he does like it then good, it's exercise and his teacher may appreciate that! Worst that can happen with trying things or tweeking old things is that it wont help, you might get lucky and it will :)