Lambton's medical officer of health says, based on recommendations from pediatricians, the province is making the right decision by making masks optional for children under grade four.
That decision was made as part of Ontario's safe return to school plan, released last week.
Dr. Sudit Ranade made the comments during a media conference on Tuesday.
"Maybe it just stems from a recognition that younger children are less likely to be able to wear a mask for an entire school day," he said. "It also may be reflective of some evidence about whether or not very young children are effective at transmitting the disease to each other and the community. So, I think it's still kind of an ongoing discussion. I would expect a lot of flux and ebb and flow in all of these different parameters."
Students in grades four to 12 will be required to wear masks come September.
Parents will have the option to keep their kids at home for online teacher-led studies.
Other safety protocols will be in place including enhanced screening and cleaning, and large gatherings will be cancelled. Common spaces like cafeterias and libraries will be closed.
The Elementary Teachers Federation of Ontario has spoken out against the province's plan, calling it unsafe and underfunded.
The Lambton Kent District School Board will unveil its final plan next week.