Troll Easy to Read Mysteries 21 Book Cassette Tape Audiobook Sets 1970s/80s

This is a set of 21 hard-to-find Troll Associates Easy to Read Mystery Book and Cassette Tape sets that come in plastic clamshell hard case like a Disney VHS. Most of the stories are based on fairy tales and designed to be able to read and listen as home or classroom readers. These were published in the late 1970s to mid-1980s. These are for early grade school students from Kindergarten to 3rd or 4th grade. These are in very good condition with only light shelf wear and some yellowing of pages due to age. The tapes and books are all complete and in good working order. 1. Case of the Great Train Robbery 2. Mystery of the Runaway Sled 3. Harold and the Dinosaur Mystery 4. Case of the Wacky Cat 5. Ghost in the House 6. Case of he Missing Cat 7. Ellen Ross, Private Detective 8. The Case of the Missing Canary 9. Tree House Detective Club 10. Case of the Missing Dinosaur 11. Mystery of the Midnight Visitors 12. My Grandma, the Witch 13. Mystery at the Zoo 14. Mystery of the Lost Letter 15. Secret of the Ghost Piano 16. Mystery of the lost Pearl 17. The Marching Band Mystery 18. The Grape Jelly Mystery 19. Secret of the Haunted Chimney 20. Secret of the Haunted House 21. Mystery at the Jellybean Factory