This collection of 24 icons was inspired from an educational project that I was working on. The modified flat style does not use any gradients nor is there more than one main drop-shadow (for the whole icon group).
The entire set includes the following vector icons: calendar, Mac & PC monitors, clock, image file, magnifying glass, map/brochure, stopwatch, crop tool, portfolio, badge/medal, lined paper on a clipboard, graph paper, lined paper pad, ledger/book, moleskin notebook, open book, pencil, colored pencil, highlighter, index cards, moon & clouds, and sun & clouds.
This collection is delivered as two fully-organized PSD files of vector assets, one for regular definition uses and one for retina specific uses. The corresponding PNG preview files are also included.