Disclaimer: I don't own anything, JKR owns everything except the plot.
It is 5:00am in wizard time and Harry and his friends were talking in the Gryffindor common room. Harry said "if we are trying to pull a prank on Snape, then why don't we just counter curse a spoon and get it to throw dung bombs at Snape." "That will never work, he could easily cast a spell on it to see the person who counter cursed its fingerprints, and find out it was us" said Hermione. Then Ron suddenly shouted "why don't we just cast the spell from a distance and not touch the spoon!!!" Harry and Hermione said at the same time "Good Idea Ron!!!"
When it was 7:00am wizard time, Harry, Hermione and Ron crept to the potions class room and took the spoon out of the plastic bag with the tweezers they used to pick up the spoon and stood back and Hermione started saying the curse when Draco walked past. Draco heard Hermione chanting the counter curse, and asked "what are you doing?" Hermione answered with a mutter "um, nothing." Draco replied with "then why are you chanting the counter curse that makes spoons throw dung bombs at the person's name you say after you have finished chanting and you were saying Professor Snape and you have a spoon with dung bombs on it in front of you?" Hermione replied "well you caught us, so go ahead and take some house points off us will you?" "Ok, I am taking 50 house points off, aaaaaaaahhhhhhhhhhhhhhh!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! You didn't chant professor Snape, you chanted Draco Malfoy!!!!! AAAAAAHHHHHHHHHHHHH!!!!!!" "Well that takes care of Malfoy, now to take care of Snape" said Harry, so Harry, Ron and Hermione ran off to play there prank on Professor Snape.