These are very basic multiplication strategies designed to introduce the concept. These Multiplication Strategies are strategies that allow students to think differently and learn to manipulate numbers in ways that allow them to feel like they are in control of numbers. Having more than one strategy to turn to gives students the freedom to think through their problems and address the best solution, not follow a rote procedure.
I highly recommend teaching multiple strategies for all mathematical operations and allowing students the freedom to choose the strategy that makes the most sense to them.
*also see my much more in-depth Addition and Subtraction Strategies
*I also have very basic Division Strategies posted