With my Year 2 class (all boys), I put up a huge poster. It was a road (with hills, forests, mountains, a sky, etc.) that went up the wall.
Every now and then, I pasted a “prize” flag. I made a car that would go up the road. I explained to the boys that our aim was to get to the end of the road, and for that, we needed to achieve specific objectives. I asked them what they thought they should work on (Being neater, lining up in order, raising their hands to speak, etc.).
Every day, the car would move (or not) according to their performance. If they reached a prize flag, they would get a prize (extra playtime, stickers, sweets, etc). Objectives and prizes are inclusive.
I also made traffic lights circles to guide students. If they got a green light, they would continue working like that. If they got a yellow, they had to change something. Red lights were a clear warning that they wouldn’t get the prize if they continued like that. For them, a red light meant the end of the world.
In the end, their behaviour improved considerably!