What do you do after you get the game guide on Wimpy Wonderland?

Answer 1

You play the game, and you have to win.

When you go back to Greg with the guide, click "examine" to reveal the way to enter easy mode, and Greg beats the game. Click on the TV he is using as a monitor, and you will play the game yourself.

(see the related question)

Answer 2

The Twisted Wizard guide is in Greg's locker in the school, which is closed. His locker is the 8th from the left under the banner, and the only one you can click on. His combination is 9, 37, 15 (it is on a slip of paper in a tree to the right of the school).

You can only enter the school when you are chasing Greg's little brother Manny. In Greg's house, pick up the Address Book, then go out Manny's window and follow his tracks left across the rooftops to Rowley's house. He will run you down with the rumble bike and continue past his house. Chase him up the tree, then right to the school. When he enters, push the trashcan onto the seesaw, then climb the tree and jump down on the right side, throwing the can onto the ledge. Push it left and you can enter the school. Chase Manny, then stop and Greg's locker and open it with the combination.

At this point you should follow Manny right to Leisure Towers, and climb up the outside to see grandpa (33-C). You can also visit Whirley Street to recover the snow shovel there. But you can also bring the Guide back to Greg's house and later visit Grandpa.