Below is an extract from the new guideline (http://www.cic.gc.ca/english/information/applications/guides/5609ETOC.asp#5609E2)
As RA/TA is an on-campus work, so I am sorry to say, from my perspective, that work experience gained during RA/TA does not help to apply CEC.
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Work experience requirements
You must have obtained at least 12 months of full-time, or the equivalent in part-time, skilled work experience at NOC Skill Type 0, or Skill Level A or B. Full-time work means at least 30 hours of paid work per week.
This work experience must have been acquired in Canada within the 36 months preceding the date your properly completed application is received by the CIO.
You do not have to be employed at the time of your application.
Note: Any periods of self-employment, unauthorized work, or periods of employment during which you were engaged in full-time study (e.g. work experience gained on a co-op, off-campus or on-campus work permit) will not be included when calculating the period of qualifying work experience. You must have had temporary resident status during the period of work experience acquired in Canada.
If you are a student and graduated from a Canadian post-secondary institution, you can gain the work experience required for CEC through the Post-Graduate Work Permit.
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