Procedure. 1  Start with a short lecture on the nature of solid, liquid, and gaseous water. 2  Your goal is to give some understanding that water molecules themselves don't change when the state of the matter changes, but that the interaction between molecules changes.
Check out our guide of what to toss when. Is your important paperwork piling up? Check out our easy-to-use chart to see what to keep, what to toss, and how to store those hard-to-replace documents. Keep tax returns, as well as supporting documents like W-2 forms, receipts, and real estate closing statements for seven years.
What to keep after filing your taxes and how long. Knowing what information to save and for how long can be confusing. As a general rule of thumb, keep tax returns and related documents for at least three years from the April 15 filing deadline. Three years: Tax return forms and schedules plus all information to support what you claimed on your return, especially records related to property, investments, or business assets (for depreciation). 2  While there are exceptions, the IRS has 3 years to assess additional tax and audit returns.