Find an instructor or if this is happening with an instructor on board fly with another one for a couple of lessons.
He may just find you the key.

You can’t learn how to fly from text.
And we shouldn’t encourage him to experiment with stuff he doesn’t understand. Especially stalls.

THIS, and joepilot’s comment.

I learned to fly 42 years ago. Stalls made me nervous at first. Instructor finally had me do the “falling leaf.” A better term is “finding out you can still fly the airplane when it is stalled.”

By staying in the stall for minutes at a time, instead of seconds, you really learn how to feel the airplane, your AoA responses, and yes...that was when I started to find my way with the rudder.

I think we did them both power-on and off. Grateful he did that...really opened my eyes.

I agree, this would be a good teaching method that the instructor could employ. Years ago, I took my father on as a student. No student was ever as important for me. I was training him in a C-150 or 152, we were at stalls and every time we go into the stall, somehow he mismanaged the rudders, and it would fall off either left or right. I tried the suggestion above, had him just sit in the burble, and work the rudder to keep the aircraft straight; I even took the yoke so he could just concentrate on the rudder and keeping it straight. I failed to get him past this point and that was the end of teaching Dad. Very sad for me personally.

One other comparison. If you have any experience in a (small) boat with a rudder, preferably a sailboat; you could more easily relate to the lack of control effectiveness in low speed flight/boating. At the speeds a light trainer stalls, the (unaffectedness) of the flight controls is really eye opening to anyone, student or experienced pilot, who has not experienced it. Full rudder, possibly even reversing from one direction to the other is certainly possible depending on how the student miss handles the stall entry. This is one of the main reasons you want to avoid stalls by being aware before you get to the stall. Better to recover at the point you recognize the problem (stall warning horn) than to fight direction control and loss of altitude during full blown recovery.

In the 152 the common reason for a huge wing drop is trying to use exclusively the ball for coordination and failure to get the yoke forward at th first break. A wing drop is a break. If you push the yoke forward the roll will stop almost instantly. As I tell my students when discussing stalls in the 152;I don’t care where the nose goes in the break, just get get that yoke forward.

The world needs accountants.