Description Level F Learning Objectives Building on the mental math skills developed in Level E, this level focuses on mastering written calculation through practice writing addition and subtraction vertically. Book (Volume/Month) - Week - Learning Content F1: Weeks 1-4 Addition up to 99 (vertical form) (Two-digit number + one-digit number, no carrying) (Two-digit number + two-digit number, no carrying) (Two-digit number + one-digit number, with carrying) (Two-digit number + two-digit number, with carrying) Achievement Test F2: Weeks 1-4 Two-digit addition (carrying in the tens place) Comprehensive review of two-digit addition Achievement Test F3: Weeks 1-4 Three-digit addition (three-digit + one-digit), (three-digit + two-digit) (Three-digit + three-digit) Comprehensive review of three-digit addition Four-digit addition (four-digit + one-digit), (four-digit + two-digit), (four-digit + three-digit), (four-digit + four-digit) Comprehensive review of four-digit addition Achievement Test F4: Weeks 1-4 One-digit subtraction (vertical form) Two-digit subtraction (Two-digit - one-digit, no borrowing) (Two-digit - two-digit, no borrowing) (Two-digit - one-digit, with borrowing) (Two-digit - two-digit, with borrowing) Comprehensive review of two-digit subtraction Achievement Test F5: Weeks 1-4 Three-digit subtraction (three-digit - one-digit), (three-digit - two-digit) (Three-digit - three-digit) Four-digit subtraction (four-digit - one-digit), (four-digit - two-digit) (Four-digit - three-digit), (four-digit - four-digit) Comprehensive review of three- and four-digit subtraction Final Test