Yesterday your child learned to raise a polynomial to a power, and today he learns to raise a polynomial to a power. It is essentially the same, only he will need to use the distributive property (what we call hippo hopping) to do the multiplication of the terms.
DoodlePoodle explains this very well on the worksheets today, so I don’t think I need to add anything. If you have issues explaining it to your child, just shoot me a question. I will reply quickly and give you some help.