Materials Needed

• Base-10 Blocks (or LEGO bricks: 10-stud long bricks for "Tens" and 1-stud square bricks for "Ones")
• A Place Value Mat (A sheet of paper split down the middle: Left side labeled "TENS" / Right side labeled "ONES")
• "Toy Order" Cards (Index cards with two-digit numbers written on them, e.g., 23, 14, 35, 26)
• Dry-erase board and marker (or paper and pencil)
• Small prize or "Toy Maker" certificate (optional, for reward)

Learning Objectives & Success Criteria

1. Introduction (The Hook & Objective)

Time: 5-7 Minutes

• Visual Demonstration: Show the number "23" written on the board.
  "This number has two parts: a Tens room and a Ones room. How many Tens are in 23? Yes, 2! How many Ones? Yes, 3!"
• Explain the rule of the Ones Room: "Only single-digit numbers (0 through 9) can live in the Ones room. If 10 or more ones gather together, they must hold hands, turn into a Ten, and move next door to the Tens room!"

2. The Body (I Do, We Do, You Do Model)

Time: 20-25 Minutes

Step A: Addition WITHOUT Regrouping (I Do)

Let's solve the robot order: 23 + 14.

1. Model with Blocks: Place the Place Value Mat in front of the student.
   • Build 23: Put 2 Tens sticks in the Tens column, and 3 Ones blocks in the Ones column.
   • Build 14 below it: Put 1 Ten stick in the Tens column, and 4 Ones blocks in the Ones column.
2. The Strategy: Always start with the ONES!
   "We always count our small items first. Let's slide all our Ones together. We have 3 ones plus 4 ones. Let's count them: 1, 2, 3, 4, 5, 6, 7! Write '7' under the ones column."
3. Next Step: Count the TENS!
   "Now, let's slide our Tens sticks together. We have 2 tens plus 1 ten. That makes 3 tens! Write '3' under the tens column."
4. Read the Answer: 3 Tens and 7 Ones makes 37! Our factory needs to build 37 robots!

Step B: Guided Practice (We Do)

Now, let's solve a trickier order together: 25 + 18. This time, we will need to regroup!

• Step 1: Build it together. Have the student count out blocks for 25 (2 Tens, 5 Ones) and 18 (1 Ten, 8 Ones) on the mat.
• Step 2: Add the Ones. Slide the 5 ones and 8 ones together. Count them together: "1, 2, 3... 12, 13! Oh no! We have 13 ones. Can 13 stay in the Ones room?" (Wait for student response: "No, only up to 9!")
• Step 3: The Magic Trade (Regrouping).
  "Let’s count out 10 of those ones. Snap them together to make a new Tens stick! Now, march that new Tens stick over to the Tens room. How many single Ones are left behind in the Ones room?" (Student should see 3 ones left). Write '3' in the ones column.
• Step 4: Add the Tens.
  "Now, look at the Tens room. We had 2 tens from the first number, 1 ten from the second number, and 1 NEW ten that we carried over. Let's count them all: 1, 2, 3, 4 tens! Write '4' in the tens column."
• Step 5: Celebrate! 25 + 18 = 43!

Step C: Independent Practice (You Do)

The "Toy Delivery" Game:

• Place three "Toy Order" cards face down (e.g., Card A: 32 + 15, Card B: 27 + 14, Card C: 41 + 28).
• Let the student select a card of their choice (Autonomy/Choice).
• The student must:
  1. Write the equation vertically on their whiteboard.
  2. Build the numbers using their blocks.
  3. Solve the addition (regrouping if necessary).
  4. Write the final answer.
• Teacher/Parent Role: Step back and observe. If the student makes a mistake, ask guided questions rather than correcting them directly (e.g., "How many ones do you have there? Can that number live in the Ones room?").

3. Conclusion & Wrap-Up (Recap & Reflect)

Time: 5 Minutes

• The Recap:
  "You did a spectacular job as the Head Toy Maker today! Let's remember our factory laws. Which room do we always add first? The Tens or the Ones?" (The Ones!)
  "And what happens if we get 10 or more in the Ones room?" (We trade them for a Ten and carry it over!)
• Celebration: Award the student a "Master Toy Maker" sticker or high-five for managing the factory's inventory so accurately.

4. Assessments (Formative & Summative)

Formative Assessment (During the Lesson):

• Observe the student’s placement of blocks. Are they correctly separating tens and ones?
• Watch the trading process during regrouping. Do they remember to *remove* the 10 individual ones when they add the new ten stick to the tens column?

Summative Assessment (End of Lesson Check):

• Provide a final "Shipping Ticket" with two problems:
  1) 52 + 24 (No regrouping)
  2) 36 + 25 (With regrouping)
• If the student can solve both problems independently using the blocks and record the correct written answers, they have mastered this lesson unit.

5. Adaptations & Differentiation