Paula Cooper

The brutality of Ruth Pelke's death defies comprehension. Chosen 
because of her hospitality to neighborhood children, she willingly 
opened her door to the teens who inquired about taking Bible lessons. 
Once inside, one of the girls hit her over the head with a vase. 
Another, 15-year-old Paula Cooper, took a butcher knife from her 
purse and stabbed her 33 times, while the others searched for cash. 
They found $10 and a set of car keys. While Pelke lay dying, they 
drove her car to their high school and took several classmates for 
joyrides.

http://www.journeyofhope.org/bills_story.htm

http://www.clarkprosecutor.org/html/death/row/cooperp.htm