The cost of living is generally high across Nunavut and it also varies from one community to the next. The territorial government (as the employer) provides a Nunavut northern allowance to educators (as negotiated in the collective agreement) to offset the cost of living.
Nunavut residents often use a yearly sealift or barge order to help alleviate the cost of living. Goods shipped by boat are much cheaper because they are not flown in. But the sealift season is limited to summer months. If hired, you should speak with your colleagues about the cost of living in your particular community and the sealift process.