dirty commit: can't get references to work correctly between any tables

app/presenters/dashboard/analyze/graph/students_by_ell.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+module Analyze
+  module Graph
+    class StudentsByEll
+      include Analyze::Graph::Column::EllColumn
+      attr_reader :ells
+
+      def initialize(ells:)
+        @ells = ells
+      end
+
+      def to_s
+        "Students by Ell"
+      end
+
+      def slug
+        "students-by-ell"
+      end
+
+      def columns
+        [].tap do |array|
+          ells.each do |ell|
+            array << column_for_ell_code(code: ell.slug)
+          end
+          array.sort_by!(&:to_s)
+          array << Analyze::Graph::Column::AllStudent
+        end
+      end
+
+      private
+
+      def column_for_ell_code(code:)
+        CFR[code]
+      end
+
+      CFR = {
+        "ell" => Analyze::Graph::Column::EllColumn::Ell,
+        "not-ell" => Analyze::Graph::Column::EllColumn::NotEll,
+        "unknown" => Analyze::Graph::Column::EllColumn::Unknown
+      }.freeze
+    end
+  end
+end