Write Skill Book?

I have been doing the mentor challenge, and the only thing left to do is write a skill book. My sim is just not up to the task. On my computer, I cannot find the option. She still doesn't have the option, and based on my practice writing, I believe she is at level 8. Nothing changes even after I shut off the PC I'm using to play the game and let her use several different machines. Is there anything specific I'm doing wrong, or is the game just being glitchy as hell? I've had other sims produce skill books outside of this challenge.