Apple Science

In this week's book, Sierra got in big trouble when she brought her mom's lunch bag by mistake because there was a knife in it. The knife was probably there so Sierra's mom could cut her apple right before she ate it so it wouldn't go brown. Do you agree? Let's see if we can come up with another way that Sierra's mom could keep her apple fresh!

Materials:

• apple slices
• lemon or lime juice (sugar water works too, but for different reasons)
• plastic wrap
• fridge and freezer

Cut the apple into slices and decide what you're going to do with each one. We kept one just on the counter (as the control in our experiment.) We put one in the fridge, one in the freezer, and one outside. Then we wrapped one in plastic wrap and coated another in lime juice. The rest of the apple slices were part of our taste test program--and they tasted great. :)

Then all we had to do was wait and observe! We took pictures of our apples after 24 hours:

And after 48 hours:

After two days, the only one that still looked edible was the frozen apple slice. (The plastic wrap one was close.) It didn't take days to see a difference, though--we definitely started to notice changes in our apples after just a couple of hours! But why? What was happening?

Cutting the apple actually damages the cells on the surfaces where you slice it. That damages the cells on the surface and exposes some of the enzymes, and these enzymes react with the oxygen in the air. These reactions slow down in cold temperatures like in the fridge or especially the freezer. And they should slow down when there's lemon juice on the surface because it has antioxidants (chemicals like citric acid and ascorbic acid that slow down oxidation reactions like the ones happening on the apple.) Plastic wrap keeps most of the oxygen away from the apple too. (Check out this article for more information, or visit this site.)

You can try your own ideas for keeping apples fresh too, or try the experiment with other fruits or vegetables. Have fun!

Zero Tolerance by Claudia Mills

From Goodreads: Seventh-grader Sierra Shepard has always been the perfect student, so when she sees that she accidentally brought her mother's lunch bag to school, including a paring knife, she immediately turns in the knife at the school office. Much to her surprise, her beloved principal places her in in-school suspension and sets a hearing for her expulsion, citing the school's ironclad no weapons policy. While there, Sierra spends time with Luke, a boy who's known as a troublemaker, and discovers that he's not the person she assumed he would be--and that the lines between good and bad aren't as clear as she once thought.

My Two Cents: Claudia Mills is a master of chapter book school stories, and this middle grade novel was just as good. This book is filled with relatable, real characters, especially Sierra herself. Middle grade readers will really root for not only her triumph, but her growth as well. Such an important look at rules and justice, but also tolerance and compassion. (Parental warning: There's a little mild language here, but it's really relevant to the story and to the character development.)

Grade Level: 5-8

Additional Resources:

• Sierra misses out on dissecting an earthworm with her science class. You can dissect a virtual worm (still gross, but not as gross) right here!
• Sierra has to study for a French quiz. You can learn to say the alphabet in French with this (cute? slightly terrifying?) frog!
• Learn more about Mayan culture (like Sierra does) by checking out this site by the authors of the Jaguar Stones series.
• Sierra is interviewed by lots of reporters for both TV and newspapers. If you're interested in journalism, check out this great list of journalism resources for students.
• One of the characters in this story wants to go to Kenya. Find out more about this cool African country here.

More to Read:

• Another story of a minor rule infraction that gets blown way out of proportion: Nothing but the Truth by Avi
• Another classic school story of a student who comes up against authority over something seemingly insignificant: Frindle by Andrew Clements
• All of Claudia Mills' awesome chapter books, including How Oliver Olson Changed the World, Being Teddy Roosevelt, and Mason Dixon: Pet Disasters