are hard to please at times. There are many great ideas on
www.mathwire.com. Check it out, maybe something there will work. Tell your students you have to do math, but you hope this will be a little different than their normal routine.
You could make a jack-o-lantern together. You demonstrate. They take notes. Then they write a "how to" paper.
You could predict the weight of the pumpkin beforehand. Then weigh it. Maybe who ever estimated the closest gets a prize. Also predict the number of seeds inside. Then divide them up and have students count their portion. Then add them altogether. Again, the person with the closest guess could receive the prize. Predict weight after seeds and pulp are removed, then weigh it again. Maybe the jack-o-lantern could be a prize. Take a flash light to put inside it, then turn off the lights and enjoy a good story. Plant some seeds in cups. See if they grow. Take some seeds home and roast them for a healthy snack the next day. Better yet get a parent to do this for the class.
My favorite story to read aloud on Halloween is The Widow's Broom. Also The Boy of a Thousand Faces is good. Then there is an old one from the 80's called Tog the Ribber or Granny's Tale. I think fifth graders would like all of these. Tog the Ribber is especially challenging because it is filled with nonsense words, so you have to use context clues to determine the meaning. I always read it twice. First time without pictures and second time with pictures. Their imaginations go wild and they want to discuss it a great deal.