9. Sam's Experiment

SAM'S EXPERIMENT 9 Sam began to perform his project. The first step was pouring dish soap into the volcano. Sam reached for the dish soap bottle. But somehow, the top popped off and soap burst out. Ms. Grinker frowned. I didn't even touch it, Sam thought. ZIPPPP! Sam looked down at his backpack. It was opening again.

Oh no, Sam realized. Orson is messing up my project to distract me. That way, he can take back the book without me being able to stop him! Sam stomped on his backpack. His sneaker pressed the zipper against the gym floor. Antonio rushed to wipe up the dish soap. "There you go, buddy," he said. Sam smiled weakly and again reached for the soap. It nearly erupted a second time, but Sam quickly placed his hand over the top of the bottle. Then he poured some soap into the volcano.

Phew. Next was the baking soda and the orange food coloring. As Sam reached for the baking soda, it toppled over— on its own! Sam hadn't even touched it! This time, Lucy stepped over to help clean up the mess. "Lucy," Ms. Grinker said, "please let Sam finish his project himself." Lucy slunk back to her own table. Sam pressed his foot harder against the backpack zipper. It continued to try to worm its way out from beneath his sneaker.

He could feel Ms. Grinker watching him. He poured the baking soda and some food coloring into the top of the volcano. "Now," Sam announced, "in one moment, I will pour in the vinegar. This last ingredient will cause the volcano to erupt." As Sam said those words, he felt the zipper squirm out from beneath his foot. His eyes shot to the floor. The backpack was open! And it was empty!