Teaching the "Which Clause"

I'm using Institute for Excellence in Writing with my public school 4th graders. While I love this program, my students are not having as easy a time as the children on the training DVD.

To further explain the Which Clause to my students, I made up the following pairs of sentences to model how to put the first sentence inside the second sentence using "which."

A.1.The slipper was made of glass.

A.2.The prince found Cinderella’s slipper on the palace steps.

The prince found Cinderella's slipper, which was made of glass, on the palace steps.

B1.The basket was full of goodies.

B2.Little Red Riding Hood carried a basket to Grandmother’s house.

Little Red Riding Hood carried a basket, which was full of goodies, to Grandmother's house.

C1.The garden belonged to a witch.

C2.The man climbed over the wall into a garden to steal some greens for his wife.

The man climbed over the wall into a garden, which belonged to a witch, to steal some greens for his wife.

D1.The house was made of candy.

D2.The children found a house and began eating it.

The children found a house, which was made of candy, and began eating it.