Final answer:
The major concern in the context of parent involvement for decades has been parent-teacher communication, which is affected by issues such as excessive paperwork and work overload. Despite more spending per student, there has been no significant improvement in test scores, suggesting that structural issues may play a role in this outcome.
Step-by-step explanation:
In the context of parent involvement, a major concern that has been present for decades is c) Parent-teacher communication. Challenges such as excessive paperwork, limited supplies, work overload, and issues with support from parents and administrators can lead to communication breakdowns between parents and teachers. The recent decades have seen increasing spending per student but without corresponding improvements in test scores, indicating that structural problems within educational systems may be undermining student success. Proposals to improve schools have been suggested, including frequent testing of students, offering incentives for high performance, and introducing choice and competition in school systems through vouchers and new school models.