Science Buddies: "Ask an Expert"

Hello,
New teacher here and my background is more in bio and chemistry, but I'm doing a physics unit this first half of the year as well as science fair and this was bound to happen. One of my students wants to test the life span of different light bulbs. But we are not quite sure how to do it with out buying an incredible amount of timers. Any ideas how to do this in a cheaper simpler way?

If you do a literature search of various manufactures of household light bulbs you will find some rather large numbers in terms of mean time to failure (in hours). Typical times are on the order of 10,000 hr which is over a year of continuous use. Some projects just can't be done in the typical time constraints of a science fair project.

For things like this, does it really matter exactly how many hours a specific unit survives? If you made observations at the same time once a day your uncertainty would be at most 24 hours or 1 day or one part in 365 or less than 0.3%. How accurate do you have to be?