As an aside, Torah Umesorah is rolling out a very comprehensive tefillah curriculum for grades K-8.
From what I've seen, this isn't just another side initiative that quickly becomes an afterthought, rather a serious curriculum with well planned teacher guides for every week of the year (different ones for each grade), and serious buy-in from the Rabbeim/Teachers.
Each grade focuses on a different part of davening and there are 5 parts. I think they are- understanding the meaning of the words, importance of davening, connection to Hashem, inspiration for davening (stories etc), and hanhaga (behavior) during davening.
They are piloting it this year at a Lakewood boys school and are planning on rolling it out to many more schools in the near future.