Go Eat Worms! by R.L. Stine

Go Eat Worms! The title echoes the words of Regina Barstow who is sick and tired of all her brother Todd's practical jokes with worms. Todd has collected worms for years and plans to win the computer prize at the school Science Expo with his worm house display. All is going well, until along comes the new kid, Patrick, who tells him outrightly that he has pinched his idea about worms for the expo and that he  has something exceptional planned. Todd is furious, and along with his friend, Danny, plots to find out about Patrick's project. One day whilst annoying Regina with worms yet again down in the basement of his house, Todd decides to cut one in half as shock value, but as Regina points out, the worms in his tank are watching! Now it seems they want their revenge. Todd's life becomes a nightmare and it seems that worms are plaguing him at every turn. This is a fast moving book following the usual cliff hanging chapter style of R.L. Stine. I read it in one sitting.