Computational Thinking Counts in Elementary Grades: Powerful STEM Teaching and Learning for the 21st Century Advancing Middle School Teachers’ Understanding of Proportional Reasoning for Teaching CAREER: Analyzing the Nexus Between Advantaged Social Positioning and Science Identity Development Among English Language Learners Girls Power in Making Group-Based Cloud Computing Proportions Playground: A Dynamic World to Support Teachers’ Proportional Reasoning Usable Measures of Teacher Understanding: Exploring Diagnostic Models and Topic Analysis as Tools for Assessing Proportional Reasoning for Teaching