Avery Economy Clear Sheet Protectors, 8.5" x 11", Acid-Free, Archival Safe, Top Loading, 100ct (75091) Musicians mark their scores in pencil, but everyone thinks of pencils. This wonderful eraser stick will cleanly erase all the marks once they are no longer need
Analog Hygrometer, 1-3/4-Inch Round Glass Analog Hygrometer for Cigar Humidors, by Quality Importers Music (even copying and printing it) is expensive, and these protectors help keep music in good condition.
Post-it Flags with On-the-Go Dispenser, Assorted Primary Colors, 1/2-Inch Wide, 100/Dispenser, 1-Dispenser/Pack Post-it flags help mark pages for easy finding of specific locations.
SanDisk Cruzer CZ36 32GB USB 2.0 Flash Drive, Frustration-Free Packaging- SDCZ36-032G-AFFP If your teacher doesn't already have one or two of these, they work very well when calibrated (go ahead and calibrate it for her or him).
Sabrent 4-Port USB 2.0 Hub with Individual Power Switches and LEDs (HB-UMLS) There are plenty of people who wish they had another USB drive or two.