I know that the high schools in my area allow up to 15 days with parent approved absences. But there is no consideration for missed assignments, other than handing them in early and tests missed are missed.
And the lower level schools are about the same, days wise. I had missed up to 30 days in high school and still passed the year with a B average (i just was very bored during high school, still did all my work and made sure I was there for test days, involved in school activites.) As long, the child is doing the work and understanding the material, a happy child is more likely to want to be in school.
Penny