A time sheet is where each individual employee write down how much time he/she has spent on each job they are working on.
A time card is less standard and could refer to more than one thing, but is normal referring to a card that an employee slips into a machine when they arrive and leave work each day – it records how many hours in total they have worked each day.
Job sheets are where the time spent by each employee on one specific job (several employees could obviously be doing work on the same job) and then the total can be added up.