Resources: You can buy various style tokens from online shops like this, or this.  

What to do: For some students placing a point in the ether that is your MIS system, i.e SIMS, Progresso, E-Portal or whatever, simply makes zero difference! 50-80 minutes is a long time, so if a student makes a mistake in between that time, they will be told that entire lesson is a failure. How about setting an individualised token based target system with some of your key students? Give your students 1 or 2 tokens per lesson, if they do things well or exceptionally well. (Relative to what they have not been able to do before.)

Ask them to place their given tokens in a secure box at the end of each day. If they meet their target, organise their parents/carers to give them a reward!?  

Variations: Marble Jar at home? Where students are given marbles by their parents/carers if they do things well, once full, they get a reward?   *Image from http://www.happytokens.co.uk