student sponsorship

Hi,
asking on behalf of my sister who would like to know which instituitions in Canada sponsor students for Higher Education. Her (twin) sons will be 15 now and will complete their 10th Grade next year. My sister is a teacher and their father works as a civil contracter in Riyadh, are keen to have their sons' Higher Education here. Would it be possible for them to come here through universities which sponsor students from abroad. If yes, pls may I know which route to pick. I would be very thankful to get any lead.

Thanks