Fire escape was patented in England in 1766. The system included a wicker basket on a series of pulleys and chains.
Fire escape ladder was invented in 1879 by J. R. Winters. He received patent number 214,224. Children could view his patent at: https://www.google.com/patents/US214224.
Margarine was patented by Alfred Paraf in 1873. The New York resident received patent number 137,564. Children could read about his process at: http://www.google.com/patents/US137564. They could do some research to see which is healthier, margarine or butter.