Whisk together flour, sugar, baking powder, and salt. In a separate bowl, mix milk, eggs, oil and chia seeds. Spray a medium skillet with cooking spray, being sure to cover the entire surface. Heat the skillet over medium-low heat. Pour a small amount of batter into skillet, making pancakes approximately 2 inches wide. Heat until golden brown, flip and allow to cook for 1-2 minutes, until the other side is golden brown. Repeat until all batter has been cooked.