The girls are at recess (a very long one, obviously) and will only leave if the school bell rings. Unfortunately, the bell is broken and there is a seagull guarding it. You will have to repair the bell. (The clapper is hidden away.)
You will have to do the following :
(see the related question)
On Big Nate island the three girls stand on the playground to the right of the school .
You can not move it.
its where the talking girls are standing
near the playground
Under the playground
where the chatty girls are.
Underneath the three girls on the playground. He won't dig there though until the girls move. You get them to move by ringing the bell on top of the school.
you can not. you have to go in it.
The Treasure is on the ground where the girls that are ignoring you are
its where the girls were "yakking"
at the playground
under the girls at the playground.