Added indexes on the frequent queries. The problem is still too many queries.

db/migrate/20150523121319_introduce_indexes.rb

@@ -0,0 +1,10 @@
+class IntroduceIndexes < ActiveRecord::Migration
+  def change
+    add_index :weights, :tournament_id
+    add_index :schools, :tournament_id
+    add_index :mats, :tournament_id
+    add_index :matches, :tournament_id
+    add_index :matches, [:w1, :w2], :unique => true
+    add_index :wrestlers, :weight_id
+  end
+end