Of course, it isn't only teachers that get sick. Sometimes in the winter I wondered if a day would ever come when ALL of my students were present! It was always overwhelming for me to keep up with the kids who were absent. I'd start out the day pretty well, setting their work aside, but then by mid-day it seems things always fell by the wayside. If their parents called and came to pick up their work I'd get it together. But, then there was the matter of getting that work back from them when they returned!
I definitely don't have a great system, and I'd love for you to comment if you do. But, I did know one teacher who seemed to have a pretty good handle on it. She put the kids in charge! If someone was absent, she'd assign another student to collect that person's work for the day. The helper would have a folder, and a sheet with each subject listed. They would be responsible for writing down what was done in each subject, and collecting any worksheets or handouts in the folder. Genius! Kids love to be in charge of other kids, and they would remind the teacher throughout the day to allow for an extra sheet for the absent kid. Then, the teacher can collect the folder at the end of the day and have something to hand the absent student when he or she returns.
The problem, of course, can come with tests and quizzes. I always tried to set aside a test or quiz for absent students when I was passing them out. But, it was always a challenge to remember to find time to give those students the test or quiz when they returned. You hate to take their recess or lunch time, but sometimes that is the only "extra" time in the day. If I was really on the ball, I'd have the kids do the make-up work in the mornings when they came in. You could even ask their parents if they could drop the child off a little early one morning to get caught up. Or, they might be willing to let them stay late in the afternoon.
This was definitely something I struggled with, and it seemed like the kids who were absent frequently were also the ones who weren't very on the ball with completing make up work! I'd love to hear any suggestions or ideas that you all have for this ongoing problem.