I start this project out with the learning target on the board - "build abstract sculptures". The students generally right away start asking what that means - so we break it down. We talk about what "build" means and they agree they know how to build things in general. Then we skip the word "abstract" and go on to talk about "sculptures". Many students will raise their hand to explain what a sculpture is. Answers I generally get are: "Sculptures are like statues" and "Sculptures are made out of things like... hard things" or "Sculptures can be at home or in a museum". Often times their descriptions are correct - but they have trouble articulating that sculptures stick out in space, sculptures are 3-D.
Instead of telling the students that sculptures are 3-D and what that means we discover it together. I will hold up a picture of a person and ask if it's a sculpture - most of my students will tell me "no". I then hold up a clay bobble head and they tell me yes. We compare and contrast the two pieces of artwork - sometimes I have to rotate the artwork to emphasize one is flat and one is not - but every time I will have a student that will notice one is flat and the other sticks out in space.
After deciding what a sculpture is we talk about abstract - this is a little tougher and easier at the same time. I give them concrete sculpture examples - sculpture of a chair (a chair from the room), sculpture of a boot (my boot on a table)... etc. Every sculpture has a concrete name - chair, boot.... Then I show pictures/examples of abstract work and ask the students to describe it. They quickly figure out that abstract is a word for things that don't have any other name - it might resemble a dog but isn't a dog, or it looks like a roller coaster...
Then after this talk, which really only takes about 10 minutes at max - I do a quick demonstration showing the students how to take strips of paper and bend, twist, fold, loop, and curl them to make their own unique abstract sculpture.
This is a high success project!