Looks like material prepared by https://www.blacklivesmatteratschool.com/ as part of their plan/goal to as you say "integrate activism into school". Not sure if it's really a leak if it's posted right on their website (https://www.blacklivesmatteratschool.com/curriculum.html)?

I definitely think that no single activism group or "area" should get an outsized influence in education. Certainly it would be irresponsible for teachers or school boards to simply take an given activists group's curriculum or material and apply them as is.

While I understand the hesitancy, especially in the early childhood context, I do wonder what you how educators should approach topical things like black lives matter?