If the teacher invited her students to her wedding, and the parents gave their permission to attend, then I see no problem with it. I may be a Republican, but I will never stand in the way of two people wanting to formally celebrate their love. If, however, the wedding took place during the school day and those children attended, I would have to expect that it would count as an "unexcused" absence for the students.
Can someone tell me exactly WHAT the academic value would be for first-graders to attend a wedding ceremony? Let's look at the PA Academic Standards for First Grade (since I work for a PA school district):
http://www.pde.state.pa.us/early_chi...ards_Final.pdf
The Standards do include a Personal, Social section, which would include Self Concept, Self Regulation, Social Regulation, and Care & Self-Reliance. Going through the standards, I find it difficult to match a wedding - let alone a same-sex wedding - to any particular content area. In order to get permission from the Central Office for a field trip, any teacher in our district would have to link the activitie(s) to specific content areas in the Standards. On that basis alone, this wouldn't fly here. I also have to wonder how the teacher could maintain student behavior, as well as provide any "teachable moments" while actively participating in her own wedding?
Now, I am too tired to review California's academic standards for first grade. If they can provide a link between viewing a same-sex marriage with the academic and social development of a young child, then I cannot complain. I will say that if it were me, I'd want to attend the ceremony with my child so I could personally answer any difficult questions my child had - OR provide a counterpoint if my views differed from that of the instructor.
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In Pennsylvania, charter schools are still obligated to deliver an education to students that adheres to the State Standards. While their method of delivery might be different, and the teaching staff less regulated, at the end of the day the Standards must be met. I suppose field trip regulations could differ, as they most probably do from state-to-state, district-to-district.