In a medium bowl, combine graham cracker crumbs, melted butter, and granulated sugar until the mixture resembles wet sand.
Press the crust mixture firmly into the bottom of a 9x13-inch baking dish to create an even layer.
Refrigerate the crust while preparing the filling layers.
In a large mixing bowl, beat the softened cream cheese until smooth and creamy.
Add powdered sugar and vanilla extract, then mix until fully combined.
Fold in the whipped topping gently until light and fluffy.
Spread the cheesecake mixture evenly over the chilled crust layer.
In a separate bowl, dissolve the strawberry gelatin mix in hot water and let it cool slightly.
Fold sliced strawberries into the cooled gelatin mixture.
Carefully spoon the strawberry mixture over the cheesecake layer and spread evenly.
Refrigerate the dessert for about 1 hour so the strawberry layer can begin to set.
Spread the remaining whipped topping evenly over the chilled strawberry layer.
Garnish with crushed graham crackers and fresh strawberry slices.
Refrigerate for at least 4 more hours, or overnight, until fully chilled and firm.
Slice into squares and serve cold for the best flavor and texture.