Ratios and Proportional Relationships

Understand ratio concepts and use ratio reasoning to solve problems.

Showing 1-10 of 21 results | Sort by: |

Resource | Resource Type Grade Level | Rating |
---|---|---|

In this problem students explore the concept of proportion by comparing the relative strengths of different mixes of juice flavor and water in a visual context. Given four mixtures represented by purple and white rectangles, students order the drinks from strongest to weakest flavor and explain their reasoning. The Teachers' Notes page offers suggestions for implementation, discussion questions, and ideas for extension and support. | Activity Grade Level: 3, 4, 5, 6+ | |

This interactive Flash applet provides a tool for exploring how gears mesh and turn relative to each other as well as the relationship between the number of teeth on a set of cogs and the number of turns they make. Users place cogs with a chosen number of teeth onto a workspace and hold down the arrow keys to see them rotate. Placing dots on teeth or gaps helps users keep track of numbers of rotations and to investigate factors and multiples. | Activity, Interactive Media Grade Level: 3, 4, 5, 6+ | |

In this investigation students explore the concept of ratios and their relationship with factors and multiples. Given an assortment of cogs (gears) with different numbers of teeth, solvers are asked to find which pairs allow for each tooth of one to fit into every gap of the other, and to form conjectures regarding which pairs would work generally. The problem is well-suited for group work. The Teachers' Notes page offers suggestions for implementation, key questions, student sheets, and links to articles, videos, and an interactive Cog Environment (cataloged separately). | Activity, Interactive Media, Video Grade Level: 3, 4, 5, 6+ | |

This tutorial provides students with experience using three types of distance scales on regional maps of North America. An introduction shows how to make use of the bar scale, the statement of equivalence, and the representative fraction (ratio) to determine distance between two locations. Printable instructions and two sets of interactive exercises are provided. | Activity, Interactive Media, Tutorial Grade Level: 5, 6+ | |

Students can use this Shockwave applet to learn basic probability concepts and to apply fraction and decimal skills. In Level 1 a number of fish are seen in a tank and users express the probability of catching a red fish as a fraction. In Level 2 the required probability is given as a fraction, and users move more fish into the tank to produce this probability. Level 3 is similar to level 2 but involves a wider range of fractions and some decimals. The Key Ideas page provides background in basic probability concepts. A set of student activity printouts (Probability) is available for further practice. | Activity, Game, Interactive Media Grade Level: 4, 5, 6+ | |

This interactive Flash applet can be used to compare and explore equivalence among fractions, decimals and percentages. It allows a child or teacher to represent fractions on one or more fraction strips, and to color individual parts. Each displayed strip can be labelled as a fraction, a decimal (to three decimal places) or a percentage; the ratio of yellow to green parts of each strip can also be displayed. It lends itself well to use with an interactive white board. A pdf guide to this collection of teaching applets is cataloged separately. | Activity, Interactive Media Grade Level: 2, 3, 4, 5, 6+ | |

This problem from the Figure This! collection of NCTM asks the student to make measurements and consider proportion and scaling to estimate the length of the Statue's nose, given the length of her arm. The activity includes links to a hint, the solution, related math questions, and additional resources. | Activity Grade Level: 4, 5, 6+ | |

In this interactive game, students use their knowledge of multiplication, division, factors, ratios, and proportions in order to determine the correct amounts of each food to be fed to the monsters. The game allows players to play at the beginning level which provides twenty-four tries to fill in twenty portions of food, with four portions given to start. The monsters give hints if an incorrect portion is given. Students may play additional levels of this game at the Lure of the Labyrinth site to which users are directed at the end of the round. | Game Grade Level: 5, 6+ | |

This iOS app includes five short math videos used to illustrate numbers on a number line, rate, ratio, and proportion. Each video is accompanied by a Learner's Guide, Comic Book Transcript, and a Teacher's Guide all in PDF format. | Lesson Plans, Mobile App, Video Grade Level: 5, 6+ | |

This 26-minute video, the second in a series of twelve, is part of the web-based course for K-8 teachers entitled Learning Math: Measurement offered by the Annenberg Foundation. Participants explore procedures for measuring and learn about standard units in the metric and customary systems, the relationships among units, and the approximate nature of measurement. In this video participants examine fundamental ideas such as unit iteration, partitioning and precision, ratio, and scale. To access the video from this link click on the VoD icon that is next to the video 2 description. | Course, Lesson Plans, Video Grade Level: K, 1, 2, 3, 4, 5, 6+ Resource is part of a PD collection |