and so on until 9+9=18. Doubling is essentially multiplying by 2. Halving is the opposite, dividing an amount by 2. Today we talked about making 2 equal groups or dividing the total in half.
I'd like to draw your attention to Problem #4 on tonight's homework. There are really two things going on in this problem (doubling and totaling).
Each morning Maria finds double the amount of money she found under her pillow the day before. On Monday she fould 1 cent, Tuesday she found 2 cents, Wednesday she found 4 cents, and the pattern continues on until Sunday.
It also states that on Wednesday she has 7 cents because that is the total of what she found on Monday (1), Tuesday (2), and Wednesday (4). So in the end when it asks how much money she has on Sunday, it is NOT asking for the amount she found under her pillow that day but rather the collective total of all the amounts from the entire week. Use this opportunity to reinforce computation skills like (finding complements of 10 OR grouping of tens and ones).