Heat oven to 350 if using a metal or glass pan, 325 if using a dark nonstick pan. 

Grease the bottom of a 9x13 pan, or bottom and sides of other pans if not using a 9x13. 

Mix cake mix, water, butter and eggs in a large bowl for 2 minutes by hand or mixer on medium speed. 

Bake as directed for the time listed on the box. 

In a medium bowl, pour boiling water on Jello and stir until the Jello is dissolved.

Poke holes into the top of the cake with a fork or the end of a wooden spoon halfway into the cake.

Carefully pour strawberry Jello evenly over the top of cake. Cool completely, about 1 hour.

Once cooled, slice strawberries in halves and cover the top of the cake with them.

Spread Cool Whip over top of cake, then garnish with more strawberry slices.