Transplanted Easterner

Hi Everyone.

I am an easterner (from Boston) transplanted here in Indiana.  Life's fine, except noone here knows how to make a decent bagel.  So I started making them myself (why not!).  I have one problem.  They fall after the boiling step.  My bagels come out flat.  They taste great.  Have that crust that fights back when you bite into it.  I am relatively new to bread baking (did it alot twenty years ago, my life got complicated).  I am looking for suggestions as to what may be going wrong.  Thanks, in advance, for any asstance anyone may offer!