Hi @vancej ...
There isn't a way to update all your assignment points on one screen. However, you can update all your due dates on one screen. Check out this Guide:
How do I bulk update due dates and availability dates as an instructor?
@James Jones has written a script that would allow you to change the points of assignments via a spreadsheet connected to your course. You can find the entire write-up here:
Adjust All Assignment Dates on One Page - Instructure Community (canvaslms.com)
Hopefully these links will be of some help to you. Sing out if you have any questions...or post your questions to James' blog if you have specific questions for him.