Requirements include earning at least 21 merit badges (including 14 required badges) and demonstrating Scout Spirit through the Scout Oath and Law, service, and leadership. This includes an extensive service project that the Scout plans, organizes, leads, and manages. Eagle Scouts are presented with a medal and a badge that visibly recognizes the accomplishments of the Scout. Additional recognition can be earned through Eagle Palms, awarded for completing additional merit badges beyond the 21 needed for Eagle, plus three months of tenure after receiving your Eagle rank. 

Three months of remaining active in the unit plus 5 merit badges beyond the 21 (26 merit badges in total) is rewarded with a Bronze Palm (after a Scoutmaster Conference and a Board of Review). 

A further three months of remaining active, plus a further 5 merit badges (31 merit badges in total) is rewarded with a Gold Palm  (after a Scoutmaster Conference and a Board of Review).

A further three months of remaining active, plus a further 5 merit badges (36 merit badges) is rewarded with a Silver Palm  (after a Scoutmaster Conference and a Board of Review).

From then on, Palms are combined:

41 total merit badges (21 required + 20 additional) = 1 bronze palm and 1 silver palm

46 total merit badges (21 required + 25 additional) = 1 gold palm and 1 silver palm

51 total merit badges (21 required + 30 additional) = 2 silver palms

And so on, in the same pattern