Add 2-digit and 1-digit Numbers, Missing Addend — Grade 2
Practice finding missing addends in 2-digit and 1-digit addition problems. Free printable worksheets for second graders.
Missing addend problems in 2-digit addition help second graders understand the relationship between addition and subtraction. These worksheets focus on problems where students find an unknown addend, such as 78 + __ = 81.
When teaching missing addend problems, start with concrete manipulatives to show what's missing. Use base-10 blocks or place value charts to visualize the problem. Teach students to use subtraction to find the missing addend, reinforcing the inverse relationship between addition and subtraction.
Add 2-digit and 1-digit Numbers, Missing Addend Worksheets
Practice finding missing addends in 2-digit and 1-digit addition with visual support and answer keys.
Teaching Overview
When introducing missing addend problems, begin with concrete examples. Use base-10 blocks to show a problem like 78 + __ = 81. Show 7 tens and 8 ones, then ask how many more are needed to make 8 tens and 1 one (81). This concrete experience helps students understand what's missing.
Next, introduce the subtraction strategy. Show that if 78 + __ = 81, then 81 - 78 = 3. Use number lines to visualize this: start at 78, jump to 81, and see that the jump is 3. Practice this repeatedly with different missing addend problems.
As students become comfortable, encourage mental strategies. Teach them to break numbers apart: 81 = 70 + 11, 78 = 70 + 8, so 11 - 8 = 3. This helps students see the place value relationships and develop mental math skills.
Finally, always encourage students to check their answers by adding the found number to the known addend. This self-checking habit builds confidence and reinforces the relationship between addition and subtraction.