If you haven't already, memorizing some basic cooking measurement conversions is really worth doing. These conversions have been drilled into my head after years of recipe testing, and this is one of the most useful ones to know!
Kitchen Fact: 1 tablespoon equals exactly 3 teaspoons
If you're scaling a recipe up or down, going from tablespoons to teaspoons isn't as straightforward as say, scaling from cups. But knowing that 1 tablespoon equals 3 teaspoons will help you scale everything — from spices to salt to leaveners, like baking soda or baking powder — properly.