**Variable**: Letters that represent numbers in algebraic expressions; called variables because the numbers they represent can vary; one or more numbers can be substituted for the letters in an algebraic expression; also referred to as the unknown.

Resources for this term:

Students compute perimeter, area, and volume using formulas and find relationships in perimeter, area, and volume after scaling.

Students explore relationships between variables in everyday situations using graphs, tables, and formulae.

Students solve a problem using two linear equations with two variables and interpret the meaning of algebraic expressions.

Which is more important: scientific freedom or the public's right to safety? Tenth grade students in a health class read three articles on the 1918 influenza pandemic genome and address the aforementioned question. The articles discuss the successful scientific research on reconstruction of the genome and the scientific community's decision to publish the complete genome. Using Template Task 8, students write an editorial that identifies a problem with publishing this research and argues in favor of or against controlling the publication of certain types of scientific research.

Students sort algebraic statements into identities, equations with solutions, and equations with no solutions, using manipulation and substitution to justify their choices.

This lesson unit is intended to help you assess how well students are able to solve problems involving measurement.

Students solve a problem of optimizing within constraints and then explore alternative algebraic and graphical approaches involving systems of linear equations.