Purchase timer light switches and install in the bathrooms, kids rooms or any room were lights may be forgotten on. The timers automatically shut the lights off after 15 to 60 minutes or whatever the time is on the one you purchase. No more lights on in the upstairs bathroom that you don't notice until after the kids are gone.
This is such a good idea and I use one in my bathroom but please check out this link regarding a recent recall just in case you happen to have this brand of timer:
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