Alternate algorithms

There is rarely only one way to solve a mathematics problem. For the assigned algorithm:

  1. Create an easy problem and solve it step-by-step
  2. Create a more complex problem and solve it step-by-step
  3. Identify key features of the algorithm
  4. Provide benefits for the algorithm

Addition & subtraction

Partial sums addition



Equal-addition subtraction



Austrian subtraction



Counting-up subtraction


Multiplication & division

Lattice multiplication



Partial products



Partial products with area model (CCSS progressions, page 15)



Big 7 division (aka. partial quotients or scaffold division)



Optional

"Standard" multiplication

Line multiplication (video: Vi Hart)

Many ways of artithmetic in USCMP