Two entries in the Simple Science series, both delightful, comprehensible, essential works for the youngest readers. The Gordons help parents satisfy childrens' endless curiosity about simple phenomena such as what makes a rainbow (Color) and what makes us warm (Fun With Heat, ISBN: 1-56847-438-5; paper 500-4). Child-friendly, colorful illustrations complement the text, providing just enough information to clarify the principles behind color and heat. Readers learn why it is hotter at the equator than at the poles, how heat moves, why animals are different colors. Simple experiments are interspersed throughout, reinforcing the concepts with hands-on learning. Adults can refer to the ""Additional Projects"" and ""Other Books to Read"" sections for more ideas. Writer and illustrator understand how young readers think and how to tantalize them with facts.