Here is my 100% Achievement guide!
Great game, and made even easier with the use of cheats if you so wish!
You can basically turn player damage down to 0 so you take no hits, and AI damage up to 400X so every fight you can smash out in seconds!
There was a potential glitch stopping people from getting the All equipment" achievement, but that has seemingly been patched and works when it isd supposed to, BUT if your still nervous, i got the achievement in a bit of a different way that it seemed to work with no issues if your still worried about it not unlocking.
Either way, hope this helps and timestamps below the video :)
Episode 1 Start - 1:40
1. Whats Your Problem? - 6:20
2. Ouch, My Head - 6:45
Collectible Chest 1 - 8:50
Side Quest 1 (The Daily Challenge) - 12:30
3. First Class Rookie - 13:40
4. The Fearsome Student - 14:50
5. Let The Games Begin! - 18:50
Episode 2 Start - 19:25
6. Dogding Master - 20:55
Side Quest (Rematch Guy Outside School) - 22:30
Side Quest 2 (An Impulse Purchase) - 23:35
Side Quest 3 (An Unexpected Crisis) - 28:10
7. Nice Reflexes - 31:35
Collectible Chest 2 - 34:10
8. Hard Working Student - 36:45
9. I Can Feel The Power - 39:10
10. Reaching New Heights - 45:05
11. The Tournaments On - 47:00
Episode 3 Start - 47:15
Side Quest 4 (Find The Glasses) - 49:50 Start/57:05 Finish
Side Quest (Rematch Guy Outside School) - 51:20
Side Quest 5 (Natures Desire) Find 3 Running guys & Beat Them - 53:45 Start/1:21:40
12. Cant Touch This - 59:10 Start/1:05:30 Finish
13. Dedicated Student - 1:22:50
14. AI Mayhem - 1:25:35
Episode 4 Start - 1:25:45
Side Quest (Rematch Guy Outside School) - 1:30:15
15. Car-Tastrophy Averted - 1:33:30
Collectible Chest 3 - 1:35:35
16. Now We're A Real Gang - 1:36:00
Side Quest 6 (Keep Your Trade Secrets) - 1:39:10 Start/1:42:35 Finish
17. Trouble Letter - 1:51:15
Episode 5 Start - 1:51:25
18. Caring Friend - 1:53:40 Start/2:01:15 Finish
Side Quest (Rematch Guy Outside School) - 2:05:35
Side Quest 7 (A Weird Place For A Game) - 2:06:40
19. Cant I Have Some Privacy? - 2:08:35
20. Assiduous Student - 211:35
21. Professional Car Wrecker - 2:17:35 Start/ 2:20:40 Finish
Collectible Chest 4 - 2:26:25
Collectible Chest 5 - 2:26:35
Collectible Chest 6 - 2:27:15
22. The Cat Is Out Of The Bag - 2:28:00
Collectible Chest 7 - 2:31:50
Collectible Chest 8 - 2:32:25
Collectible Chest 9 - 2:33:15
Collectible Chest 10 - 2:34:20
Collectible Chest 11 2:35:10
Collectible Chest 12 - 2:35:20
Collectible Chest 13 - 2:35:50
Collectible Chest 14 - 2:36:10
23. Wheres Our Baby? - 2:38:30
Epsiode 6 Start - 2:38:45
Side Quest 8 (The Underground Tournament) - 2:42:00 Start/2:47:45 Finish
Side Quest (Rematch Guy Outside School) - 2:42:20
24. Hungry For More - 2:48:10
25. Underground Business - 2:50:10
26. Bollar Spender - 2:52:30
27. Timing Expert - 2:57:00 Start/3:02:10 Finish
28. Teachers Pet - 3:02:15
29. Anikis For Life - 3:04:05
30. Devoted Student - 3:14:20
31. Ghostly Secrets - 3:14:30
Epsiode 7 Start - 3:14:40
Side Quest 9 (Retrieve The Books) - 3:16:20 Start/3:40:00 Finish
Side Quest (Rematch Guy Outside School) - 3:20:40
Collectible Chest 15 - 3:31:40 (DO NOT MISS THIS)
32. The Fellowship Of The Square - 3:48:15
Episode 8 Start - 3:48:25
(Part 1) - 3:48:50 &4:13:05
Side Quest (Rematch Guy Outside School) - 3:51:40
33. A Helping Hand - 3:52:50
34. School Champion - 3:53:10
35. Top Of The Class Student - 4:10:55
36. The Grand Finale - 4:11:40
Collectible Chest 16 - 4:12:30
Collectible Chest 17 - 4:14:00
Collectible Chest 18 - 4:14:40
37. All Geared Up! - 4:14:45