Possible Clues:

• Voting category in a high school yearbook
• Showing most intelligence in second exam about stuff read up
• Extremely bright planet moving back to front needs examination
• Sign up after second examination? Most wise
• Like Academic Challenge winners
• Most perceptive
• Like many valedictorians, classwise
• Start to swot a month before exam — that's most clever
• Maximally stylish
• States Mr Spring is the best turned out