-M-A-K-
Clues
*girls like it
*boys use it
*parents hate it
The word that fits the given clues is "makeup." Now, let me explain how we arrived at this solution.
The first clue states that "girls like it." This suggests that the word relates to something that girls generally enjoy or have an interest in. One common thing that girls like is makeup.
The second clue states that "boys use it." This implies that the word is something that boys typically utilize or interact with. Although it may not be as common for boys to wear makeup as it is for girls, there are still some boys who do.
The third clue states that "parents hate it." This implies that the word is something that parents typically disapprove of or have negative feelings towards. Makeup is known to be a subject of disagreement between teenagers and their parents, as some parents may consider it inappropriate for young individuals to wear makeup.
By considering all of the given clues and evaluating various possibilities, we can conclude that the word that fits is "makeup."