In a small saucepan, combine the sliced strawberries, granulated sugar, and water. Bring the mixture to a simmer over medium heat, stirring occasionally until the sugar is completely dissolved. Let it simmer for about 5 minutes.
Remove the saucepan from heat and allow the strawberry mixture to cool to room temperature. Once cooled, strain the mixture through a fine mesh sieve into a large pitcher to remove the strawberry solids. Discard the solids.
Add the freshly squeezed lemon juice to the pitcher with the strained strawberry syrup and stir well to combine.
Just before serving, pour in the chilled ginger ale or lemon-lime soda and stir gently to combine.
To serve, fill glasses with ice cubes and pour the strawberry punch over the ice. Garnish with fresh mint leaves if desired.
