Yes this works to "cover" any smell, it doesent affect the paint performance at all.
Usually you have to wait an hour or so, sometimes sooner, sometimes longer. It's good to wait a few days before using chalk on the blackboard to ensure full cure of the film.
Canada has Benjamin Moore, their product numbering system might be slightly different, but the product should be available.
Locate a dealer here
www.benjaminmoore.com then select Canada, and dealer locator.
Add one table spoon of vanilla extract to a gallon of paint. It will remind you of a cake in the oven when you paint. I use this trick when painting offices or other areas with lots of people to complain about the odor. I do not think this is any good to prevent actual paint allergies.