Use these clip cards like rewards cards at local stores. Do fiver assignments, and get one free! I allow my students to use these cards as homework passes once they have completed five. At other times I have allowed students to cash the tickets in for prizes or used completed tickets for a monthly raffle.
These tickets are a great positive reinforcement for work done over time, no matter the ability level. Some students may complete a ticket in a week or two, others may take a month or longer, but once they reach 5 completed assignments they earn a ticket. Great for intentional non-learns.
Having students be responsible for the ticket is a great way to teach responsibility. I usually sign my initials on the ticket to prevent forging. I have also held on to incomplete tickets and then given them to the students once 5 assignments have been done.