Lemon the oil of focus is a super versatile essential oil. If you are feeling really unfocused or trying to get your kids focused on doing their homework then lemon is your friend. You can diffuse it, smell it from the bottle apply to your wrists and temples.
Lemon is also very helpful when you have allergies or a runny nose. You can inhale from the palm of your hands, the bottle or apply over the bridge of your nose (be careful not to go into the direct sunlight with citrus oils when applying topically)
Lemon oil is fantastic for cleaning purposes. You can clean your tarnished silver jewelry with it, wipe your phone down with it, add 1-2 drops of Lemon to remove gum, sticker residue, grease spots, glue or adhesive, and crayon from most surfaces.
There is SO much more but I will save it for another day.