1st Layer: Press crushed pretzels, melted butter and 3 Tbsp. sugar in a 9 x 13 pan. Bake 10 min at 350 degrees F. Let sit till cool.
2nd Layer: Beat cream cheese and 1 cup sugar in bowl and fold in Cool Whip. Spread on top of first layer.
3rd Layer: In a separate bowl, combine Strawberry Jell-O packages with boiling water and then add sliced frozen strawberries. Stir until thick and blended. Let Jell-O set. Then scoop out the Jell-O mixture on top of second layer.