Add four cups of water to a large saucepan and bring it to a boil. Once the water comes to a boil, remove the pan from the heat and place the 4 tea bags in the hot water. Steep the tea bags for 5 minutes then remove and discard them. Do not squeeze the tea bags - allow the liquid to drain from them into the pot. Allow the tea to cool.
Meanwhile, add the frozen strawberries, sugar, and 1 cup of water to a medium saucepan and heat the mixture over medium-high heat, stirring regularly, until the sugar dissolves. Continue to cook for 10 to 12 more minutes until the strawberries begin to break down and the liquid is red.
Mash some of the strawberries against the pot with the back of a wooden spoon and allow the syrup to cool in the pot. Once cooled, strain the syrup through a fine mesh strainer into a large bowl, gently pressing the strawberries against the strainer with the spoon to get all of the liquid.
Pour the tea, strawberry syrup, and baking soda into a gallon pitcher and mix well with a long spoon. Add four cups of cold water and stir until well combined. Add fresh sliced strawberries, lemon slices, and ice to the pitcher if serving immediately, or pour the tea into glasses filled with ice. Garnish each glass with fresh strawberries and lemon slices.