Explanation
The consultant should recommend K-12 Architecture Kit as an out-of-the-box solution to track enrollments by grade for the elementary school. K-12 Architecture Kit is a solution that extends EDA to meet the needs of K-12 schools. K-12 Architecture Kit provides objects and features to track student information, such as grades, attendance, and program enrollments. The consultant can help the elementary school configure and customize K-12 Architecture Kit to track enrollments by grade using features such as Grade Enrollment or Grade Level.
Nonprofit Success Pack, Education Data Architecture, and Program Management Module are not out-of-the-box solutions to track enrollments by grade for the elementary school. References:
https://github.com/SalesforceFoundation/k12-architecture-kit
https://powerofus.force.com/s/article/K12-Architecture-Kit

Accounting Subledger is a solution that allows education institutions to synchronize fundraising data between Advancement and Finance departments. It enables them to create accounting-ready summaries of donations and other transactions from Salesforce and export them to their accounting systems1. This solution can help the college avoid manual data entry, reduce errors, and streamline the allocation of donations. Reference: Salesforce Education Cloud Academy: Consultant Fundamentals, [Accounting Subledger Overview]

Explanation
Accounting Subledger is a solution that allows education institutions to synchronize fundraising data between Advancement and Finance departments. It enables them to create accounting-ready summaries of donations and other transactions from Salesforce and export them to their accounting systems1. This solution can help the college avoid manual data entry, reduce errors, and streamline the allocation of donations. References: Salesforce Education Cloud Academy: Consultant Fundamentals, [Accounting Subledger Overview]