There is an assessment system in place which has exit level tests requiring students to pass all four tests in the 11th grade. (aypf.org)
The strategy uses a 100 % mechanical entry and exit levels for trades. (londonforexopen.com)
The collection of the memories is where the game really shines in that it forces you to think strategically about how to collect all of the memories and not just to try and exit the level as soon as possible. (thatvideogameblog.com)