Illustrative Mathematics
Ratio of Boys to Girls
How many boys are in the class? Here is an introductory exercise describing ratios. The commentary shows different ways learners can approach the problem, using a tape diagram of boys to girls and using a table. The activity includes...
EngageNY
More About Similar Triangles
Determine whether two triangles are similar. The instructional activity presents opportunities for pupils to find the criterion needed to show that two triangles are similar. Scholars use the definition of similarity to find any missing...
Curated OER
Art Class, Variation 2
Given a set of six paint mix ratios, artistic mathematicians produce an equation that relates the number of parts for blue paint to parts for yellow paint resulting new shades of green.
02 x 02 Worksheets
Proportions
Cut-and-paste a great activity into your lesson plans. Scholars analyze real-world problems involving proportions. To change things up a bit they cut-and-paste quantities to create a proportion on their way to solving the problems.