diff --git a/pom.xml b/pom.xml
index 55013c1..ced75d2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1,24 +1,38 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-  <modelVersion>4.0.0</modelVersion>
-  <groupId>de.edu.hsfulda.ciip</groupId>
-  <artifactId>tdd-pure-function</artifactId>
-  <version>0.1.0-SNAPSHOT</version>
-    <properties>
-        <maven.compiler.target>11</maven.compiler.target>
-        <maven.compiler.source>11</maven.compiler.source>
-    </properties> 
-    <dependencies>
-      	<dependency> 
-		    <groupId>org.junit.jupiter</groupId>
-		    <artifactId>junit-jupiter-engine</artifactId>
-		    <version>5.5.2</version>
-      		<scope>test</scope>
-      	</dependency>
-        <dependency>
-            <groupId>org.junit.platform</groupId>
-            <artifactId>junit-platform-runner</artifactId>
-            <version>1.5.2</version>
-            <scope>test</scope>
-        </dependency>
-   </dependencies>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>de.edu.hsfulda.ciip</groupId>
+	<artifactId>tdd-pure-function</artifactId>
+	<version>0.1.0-SNAPSHOT</version>
+	<properties>
+		<maven.compiler.target>11</maven.compiler.target>
+		<maven.compiler.source>11</maven.compiler.source>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter-engine</artifactId>
+			<version>5.5.2</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.platform</groupId>
+			<artifactId>junit-platform-runner</artifactId>
+			<version>1.5.2</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+	<build>
+		<pluginManagement>
+			<plugins>
+				<plugin>
+					<groupId>org.apache.maven.plugins</groupId>
+					<artifactId>maven-surefire-plugin</artifactId>
+					<!-- JUnit 5 requires Surefire version 2.22.0 or higher -->
+					<version>2.22.2</version>
+				</plugin>
+			</plugins>
+		</pluginManagement>
+	</build>
 </project>
diff --git a/src/main/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculator.java b/src/main/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculator.java
index e2a5450..655e166 100644
--- a/src/main/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculator.java
+++ b/src/main/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculator.java
@@ -4,6 +4,11 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 public class BowlingCalculator {
+	private static final String FOUL = "-";
+	private static final int SPLIT_NEXT_ROLL = 2;
+	private static final int STRIKE_NEXT_ROLL = 1;
+	private static final int MAX_PIN_COUNT = 10;
+
 	@FunctionalInterface
 	interface FrameScorer {
 		int score(Matcher frameMatcher);
@@ -12,6 +17,7 @@ public class BowlingCalculator {
 	private static final int INITIAL_SCORE = 0;
 	private static final Pattern SINGLE_ROLL_PATTERN = Pattern.compile("\\d");
 	private static final Pattern SPARE_PATTERN = Pattern.compile("(\\d)/ ([-\\d])");
+	private static final Pattern STRIKE_PATTERN = Pattern.compile("X ([-\\d])([-\\d])");
 
 	public int score(String rolls) {
 		int score = INITIAL_SCORE;
@@ -21,18 +27,26 @@ public class BowlingCalculator {
 		Matcher spareMatcher = SPARE_PATTERN.matcher(rolls);
 		score = scoreFrameType(score, spareMatcher, matcher -> scoreSpareFrame(spareMatcher));
 
+		Matcher strikeMatcher = STRIKE_PATTERN.matcher(rolls);
+		score = scoreFrameType(score, strikeMatcher, matcher -> scoreStrike(strikeMatcher));
+
 		return score;
 	}
 
-	private int scoreSpareFrame(Matcher spareMatcher) {
-		int frameScore = 10 - Integer.parseInt(spareMatcher.group(1));
-		String nextRoll = spareMatcher.group(2);
-		if(!"-".equalsIgnoreCase(nextRoll)) {
-			frameScore += Integer.parseInt(spareMatcher.group(1));
+	private int scoreStrike(Matcher strikeMatcher) {
+		int frameScore = MAX_PIN_COUNT;
+		for (int nextRollIndex = STRIKE_NEXT_ROLL; nextRollIndex <= STRIKE_NEXT_ROLL + 1; nextRollIndex++) {
+			frameScore = addNextRollToCurrentFrame(strikeMatcher, frameScore, nextRollIndex);
 		}
 		return frameScore;
 	}
 
+	private int scoreSpareFrame(Matcher spareMatcher) {
+		int frameScore = MAX_PIN_COUNT - Integer.parseInt(spareMatcher.group(1));
+		int nextRollIndex = SPLIT_NEXT_ROLL;
+		return addNextRollToCurrentFrame(spareMatcher, frameScore, nextRollIndex);
+	}
+
 	private int scoreFrameType(int score, Matcher scoreMatcher, FrameScorer frameScorer) {
 		while (scoreMatcher.find()) {
 			score += frameScorer.score(scoreMatcher);
@@ -40,4 +54,11 @@ public class BowlingCalculator {
 		return score;
 	}
 
+	private int addNextRollToCurrentFrame(Matcher frameMatcher, int frameScore, int nextRollIndex) {
+		String nextRoll = frameMatcher.group(nextRollIndex);
+		if (!FOUL.equalsIgnoreCase(nextRoll)) {
+			frameScore += Integer.parseInt(nextRoll);
+		}
+		return frameScore;
+	}
 }
diff --git a/src/test/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculatorTest.java b/src/test/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculatorTest.java
index 470c22d..0090bc1 100644
--- a/src/test/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculatorTest.java
+++ b/src/test/java/de/edu/hsfulda/ccip/tdd/purefunction/BowlingCalculatorTest.java
@@ -49,6 +49,7 @@ class BowlingCalculatorTest {
 		// assert
 		assertThat("score", score, CoreMatchers.equalTo(expectedScore));
 	}
+	
 	@Test
 	void frameWithSpareAddsNextRollTwice() {
 		// arrange
@@ -59,4 +60,36 @@ class BowlingCalculatorTest {
 		// assert
 		assertThat("score", score, CoreMatchers.equalTo(expectedScore));
 	}
+
+	@Test
+	void frameWithStrikeCounts10() {
+		// arrange
+		String rolls = "-- -- X -- X -- -- -- -- --";
+		int expectedScore = 20;
+		// act
+		int score = bowlingCalculator.score(rolls);
+		// assert
+		assertThat("score", score, CoreMatchers.equalTo(expectedScore));
+	}
+	
+	@Test
+	void frameWithStrikeAddsNextRollTwice() {
+		// arrange
+		String rolls = "-- -- X 2- X 8- -- -- -- --";
+		int expectedScore = 40;
+		// act
+		int score = bowlingCalculator.score(rolls);
+		// assert
+		assertThat("score", score, CoreMatchers.equalTo(expectedScore));
+	}@Test
+	
+	void frameWithStrikeAddsSecondNextRollTwice() {
+		// arrange
+		String rolls = "-- -- X -2 X -8 -- -- -- --";
+		int expectedScore = 40;
+		// act
+		int score = bowlingCalculator.score(rolls);
+		// assert
+		assertThat("score", score, CoreMatchers.equalTo(expectedScore));
+	}
 }