These printable reward cards make a great resource for relief teachers. Each child writes their name at the top (already making it easier to manage behaviours!) and teacher uses a stamp, bingo marker or small sticker to 'spot' the dots when they spot good behaviour.
The students I have taught have loved this system. At the end of each day, I usually give out a raffle ticket or similar for each five dots filled, and then draw a few lucky students to receive a tangible reward. Every child gets to keep their stamp card, which they can either show parents or their teacher on their return. I have had great success with this at all primary levels. Choose either 10 or 20 spots to fill.
The colour printables are great, but this words just as well in black/white on some vibrant coloured cards.
This resource is a wonderful one to add to your relief teaching tool kit!