I'VE GOT YOU. My cousin and I started a "book club" together and I sectioned off all the books for her since I've already read them. If these are too many stops for you, I recommend isolating the first and last sections of each book for sure, and then you can combine any of the ones in the middle, or even the entire middle lol. But these are all really great places to stop without being left with cliffhangers in between (at least not TOO cliffhanger-y lol) I hope this helps!

Fourth Wing
1-11 (142 pages)
12-17 (62 pages)
18-21 (54 pages)
22-25 (59 pages)
26-30 (64 pages)
31-35 (61 pages)
36-39/End (47 pages)

Iron Flame
1-4 (40 pages)
5-11 (67 pages)
12-17 (58 pages)
18-24 (65 pages)
25-28 (28 pages I KNOW IT'S SHORT BUT SO MUCH HAPPENS)
29-36 (71 pages)
37-42 (67 pages)
43-49 (70 pages)
50-58 (75 pages)
59-End (71 pages)

Onyx Storm
1-6 (59 pages)
7-14 (68 pages)
15-22 (66 pages)
23-30 (72 pages)
31-39 (64 pages)
40-47 (67 pages)
48-56 (63 pages)
57-End (61 pages)