Rain Drop Subtraction Within 20

Goal: To help students visualize subtraction as the "falling away" or removal of items from a set.

Materials Needed:

• Cloud and Raindrops
• Magents for the back of clouds or raindrops (optional).
• Dice (Optional)
• Playing Cards (included)

How to Play:

1. Place all the raindrops you want to use inside the cloud.
2. The "Storm" Begins
   Choose a student to come to the board. You can either provide a subtraction sentence (e.g., 10−3=?) or have the student roll a die to determine how many raindrops "fall."
3. The Falling Action
   The student physically slides the magnets from the cloud down to the "puddle" (the bottom of the board) or removes them entirely.
4. Count and Record
   Ask the class: "How many raindrops are left in the cloud?" Count the remaining magnets together. Then, write the matching number sentence on the cloud: 10−3=7

Ways to Level Up:

• The "Clear Skies" Challenge: Start with a smaller number of drops (like 5) for beginners, or go up to 20 for students ready for a challenge.
• Story Problems: Tell a story while you play. "The cloud had 8 drops. The sun peeked out and evaporated 2 of them. How many are left?"
• Partner Play: During centers, let one student be the "Cloud" (placing magnets) and the other be the "Storm" (removing them and writing the equation).
• Multiple sets of subtraction cards with differenes from 20 to 0 for differentiation within centers.