diff --git a/lib/adagrams.rb b/lib/adagrams.rb
index e69de29..28ffaf0 100644
--- a/lib/adagrams.rb
+++ b/lib/adagrams.rb
@@ -0,0 +1,163 @@
+require 'csv'
+
+# returns an array of 10 letters
+def draw_letters
+  letter_frequencies =
+  {
+    "A" => 9,
+    "B" => 2,
+    "C" => 2,
+    "D" => 4,
+    "E" => 12,
+    "F" => 2,
+    "G" => 3,
+    "H" => 2,
+    "I" => 9,
+    "J" => 1,
+    "K" => 1,
+    "L" => 4,
+    "M" => 2,
+    "N" => 6,
+    "O" => 8,
+    "P" => 2,
+    "Q" => 1,
+    "R" => 6,
+    "S" => 4,
+    "T" => 6,
+    "U" => 4,
+    "V" => 2,
+    "W" => 2,
+    "X" => 1,
+    "Y" => 2,
+    "Z" => 1,
+  }
+
+  pool_of_letters = []
+
+  letter_frequencies.each do |letter, freq|
+
+    freq.times do
+      pool_of_letters << letter
+    end
+
+  end
+
+  return pool_of_letters.sample(10)
+
+end
+
+
+# Boolean method that verifies input is valid
+def uses_available_letters?(input, letters_in_hand)
+
+  input_array = input.upcase.chars
+
+  letters_in_hand.each do |letter|
+
+    if input_array.include? letter
+      index = input_array.index(letter)
+      input_array.delete_at(index)
+    end
+  end
+
+  return input_array.length == 0
+
+end
+
+
+# returns word score based on letter value and word length
+def score_word(word)
+
+  score = 0
+
+  word.upcase.each_char do |letter|
+
+    case letter
+    when "A", "E", "I", "O", "U", "L", "N", "R", "S", "T"
+      score += 1
+    when "D", "G"
+      score += 2
+    when "B", "C", "M", "P"
+      score += 3
+    when "F", "H", "V", "W", "Y"
+      score += 4
+    when "K"
+      score += 5
+    when "J", "X"
+      score += 8
+    when "Q", "Z"
+      score += 10
+    end
+
+  end
+
+  if word.length >= 7
+    score += 8
+  end
+
+  return score
+
+end
+
+
+# returns hash of highest scoring word and its score
+# applies rules for breaking ties
+def highest_score_from(words)
+
+  best_word = {
+    word: [],
+    score: 0
+  }
+
+  words.each do |word|
+
+    score = score_word(word)
+
+    if score > best_word[:score]
+      best_word[:word].clear
+      best_word[:word] << word
+      best_word[:score] = score
+    end
+
+    if score == best_word[:score]
+      best_word[:word] << word
+    end
+
+  end
+
+  # applies rules for ties:
+  # - shortest word wins unless there is a 10 letter word
+  # - if multiple 10 letter words, the first word wins
+  shortest_word = best_word[:word].min_by do |word|
+    word.length
+  end
+
+  all_tiles_words = best_word[:word].select do |word|
+    word.length == 10
+  end
+
+  if all_tiles_words.empty?
+    best_word[:word] = shortest_word
+  else
+    best_word[:word] = all_tiles_words[0]
+  end
+
+  return best_word
+
+end
+
+
+# Boolean method that verifies word is in game dictionary
+def is_in_english_dict?(input)
+
+  CSV.read('assets/dictionary-english.csv', headers: true).each do |word|
+
+    if input.downcase == word[0]
+      return true
+    end
+
+  end
+
+  return false
+
+end
diff --git a/specs/adagrams_spec.rb b/specs/adagrams_spec.rb
index ae2ccd0..c993db3 100644
--- a/specs/adagrams_spec.rb
+++ b/specs/adagrams_spec.rb
@@ -168,4 +168,35 @@
       expect(best_word[:score]).must_equal 18
     end
   end
+
+  describe 'is_in_english_dict? method' do
+    it 'returns true if submitted word is in game dictionary' do
+      word = 'aardvark'
+
+      is_valid = is_in_english_dict?(word)
+
+      expect(is_valid).must_equal true
+    end
+
+    it 'returns true if submitted word is in game dictionary - case insensitive' do
+      word = 'AARDVARK'
+
+      is_valid = is_in_english_dict?(word)
+
+      expect(is_valid).must_equal true
+    end
+
+    it 'returns false if submitted word is not in game dictionary' do
+
+      expect(is_in_english_dict?('niugfdfl')).must_equal false
+      expect(is_in_english_dict?('hippopotamus')).must_equal false
+      expect(is_in_english_dict?('#&*123')).must_equal false
+
+    end
+
+    it 'returns false if given empty input' do
+      expect(is_in_english_dict?('')).must_equal false
+    end
+
+  end
 end