How to pull in specific content from another website

Hello, I am a high school student and manage my school news website.

I want to pull in content from this website: http://www.eaganhs.portal.rschooltoday.com/ and format it for my site. The content I want to pull is the scrolling marquee with updates/announcements. The text is dynamically changing, but is is within the same div all the time, so what code would I use to keep checking it for changes?