S.M.
My rule is if he's coughing really bad I keep him home. As the coughing can spray germs on everyone and they have no choice. Runny nose - people know germs are around and wash their kids hands because of that fact - so runny nose isn't as big a deal unless the sick kid likes to hug kids and wipe it on them. A sore throat is a stay at home sickness as it could be strep. And the biggest indicator of "contagious" is a fever. If a fever is present then I keep him home cos he's just not gonna have enough energy to heal if I wear him out - and a fever means you are contagious to others. I think kids get sicker at night cos their energy is just gone and they have no defenses left - they are exhausted and feel sicker because they are all tired out too! Hope that helps. S.