In 3 medium individual bowls, mix each pudding mix separately with 1 cup of milk, mix thoroughly, then add 1/3 container of thawed whip topping, to each pudding mix, again, mix thoroughly until combined and no lumps. Refrigerate for 20 minutes.
In the meantime, Take 24 whole graham crackers, break in half. Take 3 whole graham crackers and break into singles (broken into forths).
Lining the bottom of an 8x13 cake pan, line bottom with 12 halved graham crackers and 3 graham cracker singles. End to end of the pan.
Then spoon out and spread vanilla pudding mix gently over the graham crackers, evenly. Top pudding with 12 halved graham crackers and 3 graham cracker singles. Repeat next layer with chocolate pudding mix, then graham crackers, then strawberry creme pudding mix and finally cover pudding with the last layer of graham crackers.
Open container of prepared chocolate frosting, remove foil cover and lid. Heat frosting for 30 seconds at a time in the microwave, stirring to get frosting to a semi-liquid state for pouring, should take a total of 2 heating cycles in the microwave. Gently pour frosting over the top layer of dessert until completely covered. Refrigerate for at least 2 hours. Serve and enjoy.