George W. Bailey / Shutterstock.com Paperboard Put in Organics Bin Recycle Curbside George W. Bailey / Shutterstock.com If paperboard is greasy place it in the Organics (green) bin and it can be turned into compost. Break Down Boxes It’s easier for sanitation workers to handle and sort boxes that are broken down. It’s also easier for recycling equipment to identify paper-based material if it’s flat. Make sure to break down your boxes. Cereal & Cracker Bags Are Not Recyclable Cereal bags or box liners are generally made of HDPE (High Density Polyethylene), which is not recyclable. Find out what you can do with cereal box liners. Frozen Food Boxes Contain Plastic Frozen food boxes are made from paperboard but also contain a layer or two of plastic to help preserve their contents. Find out what to do with frozen food boxes. Milk and Juice Cartons Contain Plastic Milk and juice cartons are made from paperboard that has been lined with plastic to prevent liquid from leaking through. Find out what to do with milk and juice cartons.