Tupperware items are not cheap but they are long lasting and durable. So it is in your interests to keep them in the best possible condition.
One major problem I have found over the years is tomato stains. If you are using tomato whilst cooking with Tupperware you may find that the tomato juice can really stain the lighter coloured containers. Well here are two great ways to tackle this problem.
Spray your Tupperware with nonstick cooking spray before pouring in tomato-based sauces. This layer of oil will prevent the tomato from staining the Tupperware.
If your Tupperware has been stained red from juice or sauce, apply mustard over the area and let this sit over night and then wash in hot soapy water - gets the coloring right out fast.
If your Tupperware has become very, very sad with dirty sticky residue then you can give it a lift by soaking the whole item in bleach. Make sure you use gloves and rinse the item well afterwards. This should add new life to your Tupperware items.
For general maintenance of your Tupperware containers after use. Simply wipe them over with a cloth that has been moisten with vinegar. The vinegar will cut through any lingering grease and remove any odours.