All 3 of my kids were diagnosed with strep on saturdaymornign how long should i keep them out of school?

I have 3 children ages 10 ,9, and 6 they were all diagnosed wiht strep throat on saturday morning and started their anibotics that morning as well.How long should i kep them out of school? i called the school this morning to see if they could come toda and they said no and to call back when the nurse is in to see how long to keep them out but in the mean time i thought i would ask this community.