Level 1 (Access to lessons 1 to 60)
Level 2 (Access to lessons 61 to 120)
Level 3 (Access to lessons 121 to 180)
Level 4 (Access to lessons 181 to 240)
Level 5 (Access to lessons 241 to 300)
Level 6 (Access to lessons 301 to 360)
Level 7 (Access to lessons 361 to 420)