Back-to-school has many thinking about school supplies and homework, but parents should also focus on their child's health. The moment kids are meant to be back in the classroom, they are instead spending time at home due to illness. Back-to-school sometime means back to colds and flu as well.Missing school can impact a child's learning. If you want to help children avoid getting sick and missing school, here are some simple tips.Hands on advice.An essential and effective way to avoid catching a cold, flu or other infectious disease is simply good hands hygiene. Teaching children to wash their hands properly is the single most important factor in keeping the number of viruses they pick up to a minimum.Be sensitive to symptoms.While sometimes it's easier for parents to send sick children to school, this has consequences and can keep the vicious cycle of passing along germs alive and kicking. Many teachers complain that colds are prevalent in school because students attend when they are sick. Being alert early and looking for symptoms such as fever, cough or red eyes-this will help make the decision easier. Keeping a child home until the illness has passed will help stop the sickness cycle.Back to basics.There are two basic rules parents should follow to help their kids stay healthy - nutritious food and plenty of sleep. Make sure children eat a good breakfast and be sure to pack a healthy lunch and snack to ensure you're providing proper nutrition throughout the day. Eating nutritious foods contributes to healthy brains and learning. Also, encourage regular sleeping patterns. Growing children need at least 8-10 hours per night. Inadequate nutrition or sleep can lead to a compromised immune system and a child who's more likely to get sick.