I used the 4 serving size boxes of pudding. I know they make 6 serving size, too. Those would also work, you would just have LOTS of pudding and need to put less cool whip on top. Enjoy!

INGREDIENTS

3 small (4 serving size) packages instant pudding Prepared as directed (6 cups)
8 oz cool whip thawed
1 Box graham crackers

How to make it

Lay out graham crackers in a 9 x 13 pan
Cover graham crackers with half of pudding
Layer graham crackers over the pudding layer
Cover graham cracker layer with remaining pudding
Top with cool whip
Refrigerate overnight or for at least 6 hours
Cut & serve like cake