I found this easy but very cool project on a wonderful blog called "TeachKidsArt". It was a very do-able project for my participants and they loved the 3-D results. A different spin on a Valentine's Day art project.
Super Cool 3-D Hand Art
Cool Arts and Crafts Idea for Kids, Adults and Teens | How to Draw a 3D Hand Project - Easy Quick and Fun DIY Idea!
Blog is in Danish but has lots of op art ideas and how-tos for "3-d" pop art drawings
Heart print DIY
eerste begin van perspectief tekenen
Onderwijs en zo voort ........: 1335. Tekenidee : Diepte effect met stappenplan.