Shark Swimathon
The Ocean City Sharks have to swim 75 laps by the end of the week, and every day they figure out how many laps are left to go. Swimming and subtraction are all part of the fun!
鲨鱼马拉松——十位数的减法
数学启蒙系列是Harpercollins出品,由知名作家为孩子度身定制。
鲨鱼要有马拉松比赛了，当然是游泳马拉松，这可是鲨鱼国的一件大事。 6只不同种类的鲨鱼在一起商量，他们很想去参赛，可是没有钱。这时候，好消息来了，银行给每个参赛队提供赞助，不过需要他们游完75圈，这是个不小的数字。不过团队有6个人，大家准备一起努力。于是鲨鱼们开始自己的努力，离比赛还有4天了，6只鲨鱼分别游，第一天，一共游了14圈，队长写下来75－14 =61 第二天游了17圈，记下来61－17＝44......这样子，到了最后一天，鲨鱼们终于完成任务，拿到了参赛资金。多么自然的就把数学的概念放到故事里面了，书的最后面还有家长指导，关于做竖式减法的一些指导以及生活中怎样去练习这些，比如说看米表的公里数，算行程啊等等

Stuart J. Murphy is a visual learning specialist. A graduate of the Rhode Island School of Design, he has a strong background in design and art direction. He also has extensive experience in the world of educational publishing. Drawing on all these talents, Stuart J. Murphy brings a unique perspective to the MathStart series. In MathStart books, pictures do more than tell stories; they teach math.
Stuart J. Murphy and his wife, Nancy, live in Evanston, Illinois.

数学和体育的完美结合，完成了减法的同时，让孩子看到团队的写作，为了目标的不懈努力。