Khan Academy
You can also look for elementary level math storybooks at the library... things like the "Sir Cumference" series would be great.
I'm not as familiar with Canada as I am with the U.S., but why does it matter if she doesn't know 4th grade geometry before starting 5th grade? Will she be monitored or tested in some way, or can you just meet her where she is and teach it yourself? Can you take a step back and then catch up to the 5th grade material in her own time?