For a study, the researchers aimed to determine SARS-CoV-2 positivity and in-school transmission rates using weekly screening tests for school staff and students and describe the concurrent deployment of mitigation strategies in six schools for children with IDD. 59 students and 416 staff participated. An average of 304 school staff and students were tested per week. Of 7,289 tests performed, 21 (0.29%) new SARS-CoV-2 positive cases were identified. The highest weekly positivity rate was 1.2% (n=4) across all schools, less than community positivity rates. 2 instances of in-school transmission were identified, each among staff, representing 2% (2/103) of participants quarantined for in-school exposure. Mitigation strategies included higher than expected student mask compliance, reduced room capacity, and phased reopening. During 24 weeks that had the peak of the COVID-19 pandemic in winter 2020-21, researchers found lower rates of SARS-CoV-2 screening test positivity among staff and students of six schools for children with IDD compared to community rates. In addition, the in-school transmission of SARS-CoV-2 was low among those quarantined for in-school exposure. However, the impact of the emerging SARS-CoV-2 Delta variant on the effectiveness of these proven mitigation strategies remains unknown.