The children had great fun and it was a very popular session but, ever the engineer, Phil wasn't satisfied and worked on the catapult design to make it more reliable and robust. Not only will this prevent upset due to breakages, it will also enable the children to learn more - if a repeatable action creates a repeatable outcome (such as pulling the launcher back at a certain angle sending the ball a certain direction) they are better placed to understand the relationship between the actions and outcomes.
The Angry Birds Catapult pdf * now shows how to make a sturdy and impressive catapult using the following:
We would love to hear of someone giving this a go. Please post pictures! If you don't have access to a shot glass or the means to drill holes in it, you can always resort to egg box sections .....
* I'm not sure why the annotations don't show up well when I look at this document online, however, when it is printed out, all seems to be clear and legible!