In lower grades with no assigned desks, I have used two plastic cups with a smiley face on one and a sad face on the other. I have 10 tickets and put a ticket in the sad cup when directions or expectations aren't followed; I periodically scan and put a ticket in the smiley cup when all students are doing as expected. I announce these ticket placements saying things like, “This class earned a smiley ticket. Everyone is on the carpet and sitting correctly ready to learn.” Or, “A ticket is going in the sad cup because children are being unkind to others.”
When all ten tickets are used, I remove a happy ticket for every sad ticket and then count how many happy tickets are left. This is the number of minutes we take to do something the students like, which most recently with me in a kindergarten classroom was learning a nonsense song that I sang for them when introducing the plan. After those minutes are used, the ticket placement starts all over again.
Although this plan takes some time away from the lessons, it is far less time-consuming than spending the time required to bring kids back to task all day by talking, cajoling, reminding, etc.