diff --git a/calculator-1/src/main/java/com/codescene/calculator1/Calculator.java b/calculator-1/src/main/java/com/codescene/calculator1/Calculator.java
index 0ff2fbe..f274d42 100644
--- a/calculator-1/src/main/java/com/codescene/calculator1/Calculator.java
+++ b/calculator-1/src/main/java/com/codescene/calculator1/Calculator.java
@@ -15,6 +15,9 @@ public double calculate(double firstOperand, double secondOperand, char operator
             case ':':{
                 return divide(firstOperand,secondOperand);
             }
+            case '^':{
+                return square(firstOperand);
+            }
             default:
                 throw new IllegalArgumentException("Unsupported operation :"+operator);
         }
@@ -37,4 +40,8 @@ private double subtract(double firstOperand, double secondOperand) {
     private double add(double firstOperand, double secondOperand) {
         return firstOperand + secondOperand;
     }
+
+    private double square(double x) {
+        return x * x;
+    }
 }
diff --git a/calculator-1/src/test/java/com/codescene/calculator1/CalculatorTest.java b/calculator-1/src/test/java/com/codescene/calculator1/CalculatorTest.java
index 66c413a..258ab32 100644
--- a/calculator-1/src/test/java/com/codescene/calculator1/CalculatorTest.java
+++ b/calculator-1/src/test/java/com/codescene/calculator1/CalculatorTest.java
@@ -30,4 +30,11 @@ void divideSimple(){
         double result = calculator.calculate(1,1,':');
         Assertions.assertEquals(1,result);
     }
+
+    @Test
+    void squareSimple(){
+        // the signature isn't flexible so we repeat the same number twice
+        double result = calculator.calculate(10, 10, '^');
+        Assertions.assertEquals(100.0,result);
+    }
 }
diff --git a/calculator-2/src/main/java/com/codescene/calculator2/Calculator.java b/calculator-2/src/main/java/com/codescene/calculator2/Calculator.java
index 7c13bea..0d37f70 100644
--- a/calculator-2/src/main/java/com/codescene/calculator2/Calculator.java
+++ b/calculator-2/src/main/java/com/codescene/calculator2/Calculator.java
@@ -15,6 +15,9 @@ public double calculate(double firstOperand, double secondOperand, char operator
             case ':':{
                 return divide(firstOperand,secondOperand);
             }
+            case '^':{
+                return square(firstOperand);
+            }
             default:
                 throw new IllegalArgumentException("Unsupported operation :"+operator);
         }
@@ -37,4 +40,7 @@ private double subtract(double firstOperand, double secondOperand) {
     private double add(double firstOperand, double secondOperand) {
         return firstOperand + secondOperand;
     }
+    private double square(double x) {
+        return x * x;
+    }
 }
diff --git a/calculator-2/src/test/java/com/codescene/calculator2/CalculatorTest.java b/calculator-2/src/test/java/com/codescene/calculator2/CalculatorTest.java
index 65fae50..66f433b 100644
--- a/calculator-2/src/test/java/com/codescene/calculator2/CalculatorTest.java
+++ b/calculator-2/src/test/java/com/codescene/calculator2/CalculatorTest.java
@@ -30,4 +30,10 @@ void divideSimple(){
         double result = calculator.calculate(1,1,':');
         Assertions.assertEquals(1,result);
     }
+    @Test
+    void squareSimple(){
+        // the signature isn't flexible so we repeat the same number twice
+        double result = calculator.calculate(10, 10, '^');
+        Assertions.assertEquals(100.0,result);
+    }
 }