Eyeglass lenses are typically made from glass, polycarbonate and plastic, with plastic being the most popular option. Not only are plastic lenses a cheaper alternative, but they are lightweight and impact-resistant. The downside is that plastic lenses are more likely to scratch, and those scratches can become annoying. If the scratches are small enough, you can treat them at home and avoid having to replace the lenses.
Use a white grease pencil to draw over superficial scratches on your lenses. Fill in the scratches completely. Buff the lenses with a chamois cloth to remove the excess product.
Apply a glass etching product to your lenses with a cloth. Allow the product to sit on the lenses for the directed time and wash off. The glass etcher will remove the anti-glare and anti-scratch coating on your lenses, which is where most scratches sit, leaving the plastic beneath unaffected. Do not try this method if you want to retain those coatings.
Apply a wood polishing product such as Lemon Pledge or carnauba wax to your lenses. Rub the product into the lenses with a soft cloth for three minutes. Rinse and dry. You may need to reapply once a week.