What you need:
2 c distilled water
4 pkg unflavored gelatin
Food coloring (optional)
Heat 1 cup of distilled water to boiling.
Stir in 4 packages of unflavored gelatin (e.g., Knox) until dissolved.
Remove the mixture from heat and stir in the other 1 cup water.
Add 10-20 drops of essential oil or other concentrated fragrance.
If desired, add food coloring to tint your gel.
You may also wish to add a mold inhibitor, such as 1-2 T salt OR a small amount of potassium sorbate
OR a splash of vodka.
Pour the gel into clean baby food jars or other small, decorative containers.
The gel will set at room temperature, although you can place the air fresheners in the refrigerator for a quick set (and scented fridge).
Decorate your jars as desired and enjoy! Tips
This project requires heat, so adult supervision is required.
Feel free to scale the recipe up or down to make the amount of gel you need (e.g., 1 cup water to 2 pkg gelatin).
If you wish, you can (carefully) dissolve gelatin in concentrated liquid potpourri (no other ingredients needed) to make your air fresheners. Use a ratio of 1 cup liquid to 2 packages gelatin.
You can make multicolored gels by pouring a new color over one which has already set up (like making a layered gelatin dessert).