No. Not recommended. Maybe you are new to the forum but it has been mentioned numerous times on the photoreading forum not a good idea to try to learn photoreading on school textbooks.
You have too much at stake with school. You are much better off learning photoreading on books that have absolutely nothing to do with school.
Learn photoreading on non-school books. In the future after you have successfully activated many non-school books and have accquired a skill and a ability to activate successfully then transfer that newly acquired skill to textbooks.
Trying to learn photoreading on textbooks is asking for problems.
Photoread4me
