Expert feedback from John la Roche, ex-director of Water for Survival and Dr Hugh Thorpe, University of Canterbury.

1. Samuel, Teagan and Max

Effectiveness  You have made a very simple device and demonstrated how it works.  It is small and compact and it appears you need one person to operate it for the person whose hands are dirty.  This is an excellent idea as it would avoid the device being contaminated by dirty hands.
Durability  You do not mention how the device is made but it appears to be a plastic container with a squirt top.  This should be easy to find and use in PNG.
User Friendliness  Provided someone is prepared to operate and squirt the device at dirty hands, the device should be very user-friendly and it is obviously simple to use.

Communication  Your video is an excellent way of demonstration how to use the device but PNG children would need to learn about the importance of cleanliness.

2. Bryre, Jade and Jay

Effectiveness  You have put a lot of effort into thinking about your invention.  Leaving the ice-cream container out to catch rain is a good idea but perhaps there might be some nights with little rain when some other source of water might be needed. 
Durability  You have thought about using easily available and low cost PNG materials.  This is important for finding replacement when items wear out or become damaged. 
Under Friendliness You mentioned using other containers and straws to allow enough water to flow for hand washing.  This is a good idea but possibly a little complicated to work for children in PNG who might be a bit rough in their handling of the device.  What a good idea to have soap and a towel near by.  Well done on thinking what to do with the waste water.  This is important and feeding animals or watering the garden would be a very good use for the waste water.

Communication Your video describes how the the invention works.  The children using it would need to know how important it is to be clean and wash hands.

3. Razan, Maia and Max

Effectiveness  You seem to have a soft plastic container with water in it on a stand feeding a tube down into a container where hands are washed.   This is a nice simple method, but you would need to make sure the soft container have plenty of water in it for all the children who need to wash their hands.
Durability  It looks as though all the materials are those likely to be available in PNG.  Using easily available low cost local materials is important and you have thought about this.
User Friendliness  It might need to be a little higher off the ground to make it easier for people to wash their hands. 

Communication  Your video is a good way to show how your invention should be used.  Children would need to know how important it is to have clean hands.

4. Alina,Nabeel and Nicola

Effectiveness  You have thought about lots of children wanting to wash their hands by having lots if containers and cups.   This is good thinking.  Your system with lots of cups and containers is a good idea provided someone can collect the cups and containers and wash them for the next day's use.
Durability There should be no problem finding cups and containers in PNG and to replace them when they are worn out or broken.  However there may not be large numbers available at small schools so they would need to be washed daily  for re-use.
User Friendliness Your system with straws cups might be a little complicated for children to use.  However hand washing is so important that the children would need to learn how to use it and be careful.

Communication The video is a good way of demonstration how your device works but children would need to know the importance of cleanliness.

Effectiveness  You have developed a good relatively simple device to provide enough water to wash hands.   Perhaps you might need a larger container for the clean water so when all the children come out of class and need to wash their hands there would be enough to go around.
Durability Using readily available plastic containers is a good idea and they should be easily found in PNG.
User Friendliness Your device would be easy to use although it might be better on a stand at a more convenient height for the children to use.

Communication  Your video is a good way to show the children how to use your device.  They would need to know about the importance of cleanliness.

Effectiveness  Your device seems to have two containers for washing hands - one for the dirty hands and a cleaner water to rinse then with a cloth.  This is a god idea provided you have enough water available and the rinsing container can be kept clean.
Durability  You have chosen plastic containers that should be easily found in PNG.  
User Friendliness  There might be a few problems in keeping your containers filled and the rinsing container clean.  But it is a simple device and should be easy to use.

Communication  Your video is a good education device but children would need to know how important it is to have clean hands.

7. Logan, Ben and Tristan

Effectiveness   What a nice simple device you have made.  Easy for someone to und the cap to let water flow, but you would need someone to operate the device for the person who wants to wash their hands.  This will be a good way to prevent contamination of the device by the person with dirty hands.
Durability  It is not clear what sort of container you are using but there are lots of plastic containers available in PNG that should be suitable.
User Friendliness You have thought of a good system, the only problem might be to get one of the children with clean hands to operate the bottle.

Communication You have a simple easy to use device and the video will show how it is used.  The person operating the device will need to have clean hands and he/she can make sure others wash their hands properly.

Effectiveness Your device should be able to to provide for good hand washing but you would need someone to pour the clean water into cups for the person with dirty hands to use.
Durability  You have chosen plastic containers and cups that should be easy to find but you might need to clean the cups and containers at the end of the day.
User Friendliness   Your device might be a little complicated for PNG children.   Perhaps you could pour straight from the bottle into the hand washing container. 

Communication  You have prepared a good video to show how your device works.  You would also need to make sure those using the device understand how important it is to have clean hands, particularly the person pouring from the bottle.

9. Zoe, Leah and Nate

Effectiveness  What a nice simple device with one person feeding soapy water to the person with dirty hands.    You would need to have a person to pour the soapy water into the funnel but this is a good idea for keeping the device clean.    You would need to make sure there was enough water for all the children to be able to wash their hand.
Durability  You have used items that should be readily available in PNG.
User Friendliness   Your device should be simple to use and the person washing their hands should be able to get a good wash.

Communication Your video makes it easy for children to see how to operate your device but it would be important to emphasise the importance of having clean hands, particularly the person dispensing the hand washing liquid.

Effectiveness Your device is nice and simple but it might get contaminated by people who have dirty hands.  I was not sure why you needed string but having soap and a towel available is a good idea.
Durability  You have chosen plastic containers that should be easy to find in PNG.
User Friendliness  Your description of using the device sounded a little complicated but it should be possible to have a good hand wash.  Well done to think about using the waste water on the garden

Communication   The video is a good way to show people how to use your device but you would need to make sure everyone know how important it is to wash hands when they are dirty.