The School Store is located in the Media Center and GMHS students must have a valid pass to purchase supplies. The store is open Monday through Thursday and opens at 7:15 am and closes at 4:15 pm. Available supplies are as follows:
| Pack of Colored Pencils | $1.75 |
| Black and White Composition Book | $1.50 |
| Crayons | $2.00 |
| Eraser | $0.40 |
| Sticky Color Flags | $1.75 |
| Clear-Vu Folder | $0.50 |
| Color Pocket Folder | $0.30 |
| Glue Stick | $1.25 |
| Glue Bottle | $1.50 |
| Pack of Graph Paper | $1.50 |
| Highlighters | $0.40 |
| Hornet Pencil | $0.35 |
| Index Cards | $0.75 |
| Index Cards (Wire Bound) | $1.50 |
| .05mm Lead Refill | $0.50 |
| .07mm Lead Refill | $0.50 |
| Sharpie Marker | $1.00 |
| Fine Tip Marker (Color) | $1.00 |
| Large Tip Marker | $1.50 |
| Notebook Dividers | $1.75 |
| Pack of Notebook Paper | $1.75 |
| Magnetic Organizer | $1.50 |
| Combination Pen | $0.75 |
| Sticky Grip Pen | $0.35 |
| Mechanical Pencil | $0.60 |
| Mechanical Pencil (Gem) | $0.60 |
| White Poster Board | $0.50 |
| Folding Rulers | $1.00 |
| Science Board | $2.75 |
| Science Board Titles | $2.50 |
| Science Board Topper | $1.50 |
| Science Board Totes | $1.25 |
| Box of Tissues | $1.00 |
| Wite-Out Pen | $2.00 |