You still can, just within the boundaries of the syllabus. You can't however skip from stage to stage. So, if you're lacking some cross-country time and want to "tailor" your students training to milk the student for some cross-country, then no you can't do that 141. (not implying that you, I, or anyone else milks students. used more or less for effectiveness) Likewise if a student wanted to get out of the practice area and do maneuvers as they fly cross-country to a hamburger joint 50+ miles away, you could do that part 61. Not so much 141 unless that destination airport is part of the lesson plan.

keep in mind the original poster is a student not a cfi. And yes de727 is correct in that 61 instructors have a LOT more freedom than 141. But again, it depends on the school, their instructors, and ultimately you as a student. Research both and find a school that suits you. Every school is different. Don't let one bad 141 or 61 school spoil your perception of either.

As a CFI though, 141 is way to go as far as instructing. In my experience, students seek out the school and students fall in the cfi's lap. part 61 may not be so easy unless you work in a high density area such as Houston, etc. But as I mentioned every school is different regardless of 61/141