Using rubbing alcohol is a great way of removing sharpie out of white shirts and other clothing.
To get Sharpie out of white shirts or other clothing take a cloth or sponge and dip it in some rubbing alcohol and then dab the rubbing alcohol around the sharpie stain and then dab the rubbing alcohol directly onto the sharpie stain.
Before you use the rubbing alcohol it's best to put a paper towel underneath the shirt where the stain is so that the sharpie ink will transfer onto the paper towel.
You may need to dab the rubbing alcohol a few more times onto the stain to remove the sharpie stain all the way but after a few tries the sharpie stain should be fully removed.
Then just run the shirt through a wash cycle in the washing machine and it should come out clean.
I've had great luck using rubbing alcohol for removing permanent marker and sharpie stains from white shirts and other clothing.