Place Value 1: http://youtu.be/vKc61vhFMyU
Explains place values for whole numbers, base ten, powers of ten, expanded form of a number, state place value of number.
Place Value 2: http://youtu.be/n_VoV1mOPI0
Shows how to write a number in words, and how to write from words to a number.
Rounding Whole Numbers: http://youtu.be/vNsmn4SMD4k
Shows how to round whole numbers to a certain place value.