Oh wow, hi! Fancy running into you here! I hope you enjoyed Montreal!
To answer your questions:
Other than moderating for inappropriate content, the learning activities are whatever teachers think is useful. Whether it's aligned with curriculum standards is to the teacher's discretion. However, that being said, a month ago in Quebec we had a 'congress' of teachers from all around the province gather to create content with other teachers of similar disciplines, with the blessing of their respective schools and school boards. We are planning many more of these assemblies and we are developing a partnership with the province to encourage teachers to create content that's closely aligned with the provincial curriculum.
When we have a commanding audience in the US, we will reach out to whomever to aid us in creating or curating CCSS related material.
As for our company, students do not pay and teachers are not paid. (At least not by us.) Teachers' content will always be marked with their authorship giving proper credit where it's due and we have faith that great teachers will teach. Our hope is that teachers will find joy in witnessing the reach of their wisdom and that other teachers will share their wisdom in turn, so that everyone wins. Especially the student.
Our platform is always free to use for individuals and we only charge schools or school boards when we set up private portals for greater privacy controls. We also provide training and strong customer support for paying organizations.
I hope that answers your questions! I'd be happy to take more here (if it's appropriate) or at ytakahashi@challengeu.com!