In Fairfax, if a child has an unexused absence of more than 15 days, they are basically expelled by the registrar (and you have to re-register them). Six days is no biggie, but my understanding is that the teacher has discretion, ie, can refuse to let your child make up missed tests. If the teacher is cool, you'll be fine. I've known families to take a week at Disney. Your reason is much better.