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TOO HOT? TOO COLD? Keeping Body Temperature Just Right

Curriculum Links
  • Language Arts: comprehension strategy--compare and contrast, main idea/details strategy, cause and effect relationships
  • Science: Life science--animal adaptation and classification

  • Next Generation Science Standards
  • 3-LS4-2. Use evidence to construct an explanation for how the variations in characteristics among individuals of the same species may provide advantages in surviving, finding mates, and reproducing.
  • 4-LS1-1. Construct an argument that plants and animals have internal and external structures that function to support survival, growth, behavior, and reproduction.
  • 4-LS1-2. Use a model to describe that animals receive different types of information through their senses, process the information in their brain, and respond to the information in different ways.

  • Prizes and Awards
  • AAAS Science Books and Films, Picture Book Finalist for 2014.
  • NSTA Outstanding Science Trade Books for Students K-12, 2014
  • Junior Library Guild selection for 2013.
  • Children's Book of the Month Club selection for 2013.
  • Children's Projects

    Which Cools the Fastest? Here is an experiment you can do. You will need two thermometers. Wrap one in a wash cloth and the other in a paper towel. Put them in a refrigerator. After ten minutes, take them out. Which thermometer shows the warmest temperature? Which shows the coolest? What conclusions can you draw? You can try comparing other materials to determine which ones make better insulation.

    Three Cool Activities for Too Hot? Too Cold?: Click here to go my December 2012 post at Unabridged (the Charlesbridge blog at for more activities and commentary on the book.

    Related Books by Caroline Arnold
  • A Warmer World: From Polar Bears to Butterflies How Climate Change Affects Wildlife
  • Reviews

    Kirkus, January 2013 Starred Review
    A fascinating and thorough look at how both animals and humans regulate their body temperatures. Beginning with the difference between warmblooded and coldblooded species (the terms endothermic and ectothermic are introduced but not used), Arnold devotes spreads to such topics as muscle movements, sweating, the shrinking and expanding of blood vessels in the skin, fat, body coverings, and the size and shape of an animal. Behavior can also affect body temperature: animals or humans can seek/avoid the sun or a breeze, cool off or warm up with water, find shelter, or hibernate/estivate/migrate. The one misstep is a minor quibble--a sentence incorrectly states that "No animal can live if its body temperature falls below freezing." The copyright page lists the illustrations as having been done in watercolor and Photoshop, but readers would be hard-pressed to see any evidence of digital artwork here. The spreads and spot illustrations have that blurry, batik quality of watercolors that lends itself so well to nature scenes, while the insets are well-delineated, allowing readers to understand the structures discussed in the text. Every animal is labeled, making this a great jumping-off point for further research into readers' favorites. A glossary and author's note round out the text. A stellar addition to a rather empty shelf. (Nonfiction. 6-10)

    AAAS Science Books and Films, November 29, 2013
    Set a thermostat just a few degrees too cold or hot, and there will be no shortage of complaints. But put the same people on a sun-soaked beach or fresh-packed ski slope, and they'll enjoy the temperate extremes. "Warm- blooded" (endothermic) animals, including mammals and birds, can regulate their temperatures in response to their surroundings, whereas "cold-blooded" (ectothermic) ones cannot and must exploit their environment. The contrast between these responses forms the thread Arnold uses to tie together and explain how humans and other animals keep their temperature just right. The large ears on the fennec fox, the panting of a dog, and the sweating of exercising humans are all examples of mammals' cooling tricks; they may generate heat by shivering or the conversion of brown fat to energy. In contrast, coldblooded animals may expose more surface area to heat or cool up, by, respectively, capturing more sunlight or letting the heat escape. The author also discusses body shape, coverings such as hair and fur, burrowing into the ground, hibernating, and the need to migrate. The presentation of content in bite-sized chunks with many helpful illustrations makes the book appropriate for a wide range of ages. It can be described as a hot success or a cool read-- either way, it gets its audience's temperature just right. Marc Lavine

    Booklist, April 1, 2013
    With an open, relaxed format and short blocks of simple text, much of it strategically placed so as to appear as captions for the copious illustrations, this should draw readers regardless of their previous interest in the topic. Beginning with a sound explanation of the difference between warm-blooded and cold-blooded animals, Arnold then contrasts methods that humans and a variety of other animals use to adjust body temperature, such as sweating, body movement, and so forth. The proper terms endothermic and ectothermic are included. Concluding pages give information about temperature-controlling methods unique to animals, like hibernation and migration. The appealing assortment of animals is made even more so by Patterson's attractive watercolors sprinkled throughout. This would work well as an introductory read-aloud and will answer almost any questions young readers might have on the topic. Randall Enos

    NC Teacher Stuff, January 20, 2013
    People and animals live in hot places and cold places all over the world. In every climate, people and animals find ways to keep their body temperatures just right. To quote the great philosopher Goldilocks, this book is not too hot or too cold. It is just right. After the introduction to the book, the difference between warm-blooded and cold-blooded animals is explored. Science teachers will be happy that the terms endothermic (warm-blooded or animals that produce their own body heat) and ectothermic (cold-blooded or animals that need heat from outside their bodies) are introduced. The next section explains how our bodies keep us warm or cool. My students know that they shiver or have goosebumps when their skin is cold, but they would have a hard time explaining why this happens. Now they can know that muscles "shiver" to contract and generate heat in their body. They will also know that tiny muscles in the skin tighten and make the lumps that make "goosebumps". Students will also be intrigued to know that cats curl up in a ball when they are cold and stretch out to cool off their bodies. This explains why my cat stretches in front of the fire. The last section of the book discusses what people and animals do to be warm or cool. There is a great explanation of estivation, which is like hibernation except it occurs in the summer. For example, lungfish burrow into the mud to avoid the lack of water when the river dries up. I was also fascinated by the common poorwill. It is a bird that hibernates for weeks or months at a time. Can I gush? This is a fantastic book. It is filled with so much information that will interest your students. Too Hot? Too Cold? will explain many body functions that students experience, so connections will abound. Caroline Arnold does a terrific job of providing examples for all of the concepts in the book. Kids love animal books and they will love this book. Find a copy of Too Hot? Too Cold? for your animal and human body units. Jeff Barger (second grade teacher)

    School Library Journal, February 2013
    Gr1-3. This well-organized title uses a picture-book format to take a relatively boring concept-temperature regulation in people and animals-and make it downright interesting. Arnold touches on all aspects of the subject, from the internal (fevers, muscle contraction, goose bumps, sweating) to the external (sunbathing, burrowing, hibernating, migrating). The text is clear and readable, and the design includes plenty of white space to avoid overwhelming readers. The illustrations, though appealing, feature muted tones that are unlikely to grab readers' attention. The lack of an index or table of contents lessens the book's usefulness for reports. Kathleen Kelly MacMillan, Carroll County Public Library, MD

    IRA, Reading Today Online, March 2013
    Looking at both humans and animals the author talks about how creatures stay warm. Many science books for early readers present topics on hot and cold, but this book is really discussing how bodies work at keeping a safe temperature not only for comfort but also survival. Arnold presents facts about sweating as a heating and cooling activity, how blood expands and contracts within our veins to keep blood pulsing and bodies warm. She goes on to explains the facts about body fat, hair, fur and other body coverings, shelter, the use of water and other liquids, and even behavior and activity levels that create heat to stay warm or cool. The discussion of a variety of animals and their migration or hibernation patterns are presented and each animal is labeled and easily identified. A glossary and author notes are found at the end of this very informative book. Teachers will find several temperature related activities that go along with this book at the publisher's blog, Unabridged. Karen Hildebrand, Ohio Library and Reading Consultant

    Library Media Connection, Nov/Dec 2013
    Arnold and Patterson have created a quality nonfiction book that teaches young children about regulating their body temperatures. Throughout the book, the author presents the topic and how it relates to humans and animals. For example, when covering the topic of sweating in humans, the author compares it to the panting of dogs. All types of animals are covered: mammals, reptiles, and insects. The illustrations are age-appropriate in their simplicity yet still complete in the parts that are discussed. The book is constructed in such a way as to read like a primary level story, with the facts necessary for a nonfiction book. There is a glossary of terms as well as an author's note on the last page. Laura McConnell, Children's/Teen Librarian, East Morgan County Library, Brush, Colorado Recommended