Yeah, what Gavin513 said. In my state and probably others, getting into a nursing program is pretty competitive. The pre-nursing classes (in Oregon) are pretty standardized here so that a student will need to have writing composition, college algebra, A&P, micro, developmental psych, nutrition, and biology that included a genetics component. All have minimum grade requirements and points are given based on grades in those courses. My community college required a CNA certification to even apply to the program. Now it is offering several points towards program acceptance for working a considerable amount of hours as a CNA. Because of very limited resources (instructors and clinical sites) nursing schools don't want to waste time with students who aren't completely up to speed at the time they begin either a 2 year ADN program or 3 year BSN program. Just like everything else, a lot has changed in nursing over the last 30 years.
The OP is right, go for the gold. If you are struggling early, go after all of your resources. Heck, You Tube has tons of videos that can help explain a process that isn't coming across so well from your college instructor.