After searching on the internet I found these definitions for both the terms:
Modular examination:
A GCE, VCE, GCSE, key skills or GNVQ scheme of assessment in which the components may be taken over more than one examination series (as opposed to a linear examination).
Linear examination:
An examination in which all examination components are taken in one examination series.
(both definitions taken from
http://webcache.googleusercontent.com/search?q=cache:VhqyDZJ...Given the definitions above, I think the nearest Arabic equivalent to "modular assessment" is التقييم المرحلي. As for "linear assessment", how about التقييم النهائي?
Any suggestions are welcome.