INSTEAD of "twiddling my thumbs",

… I spend my SPARE TIME devising VARIOUS mathematical-ACTIVITIES.
For example:

(1 + 2)^3 x 4 divided by 5 + 6 - 7 = ?

(… THIS demonstrates the "Order of Operations":)

((… Please (Parentheses) Excuse (Exponents) My (Multiplication) Dear (Division) Aunt (Addition) Sally (Subtraction))

ANSWER:
1 + 2 = 3
3^3 = 27
27 x 4 = 108
108/5 = 21.6
21.6 + 6 = 27.6
27.6 - 7 =    20.6 


...