Homework on adding within 100, split by what gets added. Students add multiples of ten to two-digit numbers after the worked example 34 + 20 = 54, add ones with a yes-or-no check on whether they composed a new ten in problems like 47 + 5, and close with Leo's story: 38 toy cars plus 7 from his grandmother, with a work-showing box for drawing tens and ones.
1.NBT.4
“Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.”
The parts follow the standard's own clauses: a two-digit number plus a multiple of 10, then plus a one-digit number, with the compose-a-ten question asked on every Part 2 item.
The rule at the top: put tens with tens and ones with ones, and look closely at whether the ones make a new ten.
Problems in the style of the printed example 34 + 20 = 54 (3 tens + 2 tens = 5 tens), starting 42 + 20 and 50 + 26.
Each item pairs a sum with the line 'Made a new ten? Yes / No'. 53 + 4 takes a no; 47 + 5 takes a yes.
Question 11 gives Leo 38 toy cars and 7 more for his birthday. A box invites drawn tens and ones or a number sentence, and the answer line reads 'Leo has ______ toy cars in all.'
The checkbox is the homework
Tell students the yes-or-no line counts more than the sum. Parents helping at home then focus on the regrouping idea, not the answer.
Mark Part 2 in two colors
Sums right but checkboxes wrong means answer-getting without place value. That group needs base-ten blocks before the next lesson.
Leo as the plenary
Rework 38 + 7 on the board when the homework returns: 38 + 2 gets to 40, then 5 more. It is Part 2's checkbox made visible.
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