Alex and Abi learn about reusing, recycling and repurposing using Maurice's Marvellous Recycling Machine. Professor Veena Sahajwalla visits to talk about her invention, green steel. Through The Windows we meet some koalas.
| Name | Type | Role | |
|---|---|---|---|
| Abi Tucker | Guest Star | Host | |
| Alex Papps | Guest Star | Host |