We plan to take payments up to our first cutoff date, then the price goes up. Can I change the price manually on our event price page? or do I have to create a new event when the price goes up?

For easier record keeping purposes, I always suggest that you simply deactivate the activity with the old price (DO NOT DELETE IT, JUST DEACTIVATE IT) and then create a new one to make active with the new cost. That way, your reports will be broken down by activity and you will also have the details as to how many were paid at each price. Be sure to click the Publish button to take all of the changes live in the site.

Thank you.
It been a few year, so I forget, does an email automatically send to classmates after my event is Published? or do I need to send something in addition to tell them registration is Open?

An email does get sent out.... but I would follow that up with a custom email to the class at some point as well.

perfect. Thank you so much