diff --git a/lib/scrabble_score.rb b/lib/scrabble_score.rb
index e69de29..07065d7 100644
--- a/lib/scrabble_score.rb
+++ b/lib/scrabble_score.rb
@@ -0,0 +1,23 @@
+class ScrabbleScore
+  def self.scrabble_test(string)
+    if string == nil
+      0
+    else
+      string =string.downcase
+    letter_score={
+        /[aeioulnrst]/ => 1,
+        /[dg]/ => 2,
+        /[bcmp]/ => 3,
+        /[fhvmy]/ => 4,
+        /[k]/ => 5,
+        /[jx]/ => 8,
+        /[qz]/ => 10
+    }
+      word_score = 0
+      letter_score.each do |letter , value|
+        word_score += string.scan(letter).count * value
+      end
+      word_score
+  end
+  end
+end
\ No newline at end of file
diff --git a/spec/scrabble_score_spec.rb b/spec/scrabble_score_spec.rb
index e69de29..453aa2b 100644
--- a/spec/scrabble_score_spec.rb
+++ b/spec/scrabble_score_spec.rb
@@ -0,0 +1,43 @@
+require "scrabble_score"
+describe ScrabbleScore do
+  describe ".scrabble_test"
+  context "given an empty string"
+  it "returns 0" do
+    expect(ScrabbleScore.scrabble_test("")).to eql(0)
+  end
+
+  context "given a space"
+  it "returns 0" do
+    expect(ScrabbleScore.scrabble_test(" ")).to eql(0)
+  end
+
+  context "given nil"
+  it "returns 0" do
+    expect(ScrabbleScore.scrabble_test(nil)).to eql(0)
+  end
+
+  context "given \"a\""
+  it "returns 1" do
+    expect(ScrabbleScore.scrabble_test("a")).to eql(1)
+  end
+
+  context "given \"f\""
+  it "returns 4" do
+    expect(ScrabbleScore.scrabble_test("f")).to eql(4)
+  end
+
+  context "given \"street\""
+  it "returns 6" do
+    expect(ScrabbleScore.scrabble_test("street")).to eql(6)
+  end
+
+  context "given \"OXYPHENBUTAZONE\""
+  it "returns 41" do
+    expect(ScrabbleScore.scrabble_test("OXYPHENBUTAZONE")).to eql(41)
+  end
+
+  context "given \"alarcity\""
+  it "returns 13" do
+    expect(ScrabbleScore.scrabble_test("alarcity")).to eql(13)
+  end
+end
\ No newline at end of file