Pencils Put in Garbage Check the Label Mechanical pencils are usually either metal or mixed plastic. Both should be recyclable, but often both are too small to be sorted, or are made of a mixture of metals and plastics, making them impossible to recycle. Check the packaging on your pencil packs to see if they are labeled plastics #1, #2, #3, #4, #5, #6 or #7 and follow those instructions. Ways to Reduce Use Mechanical Pencils Instead Cut down on the waste caused by wooden pencils, which can’t be recycled, by switching to mechanical pencils. They can be reused indefinitely, but are usually not recyclable because they are made of plastic #6. Purchase Recycled Pencils Cut down on the number of trees that are used to make wooden pencils with a recycled pencil. TreeSmart, for example, makes their pencils out of recycled newspaper.