Well done Chas! When you consider an intro of "sharps" (soon I think for the oldest), you may want to consider a small EMT shears. Blunt tip even passes most (but not all) anti weapon school policies. As to water filtration ( again, when appropriate ), take a look at the Seychelles advanced purifier straws and bottles. Great utility for a good price. With the bottles, you can store the filter unit in a verysmall zip seal bag, until needed. That allows use of the bottle as a day to day water supply.