Use number lines to support number sense. Make a number with painter's tape and use 50 and 100 as benchmarks. Great way to teach number place. Could be adapted for whole class instruction.
Strategies for teaching addition and subtraction using open number lines, a Common Core grade math skill
Math Coach's Corner: Open Number Line Addition - here's the handout.
The Classroom Key: Open Number Lines Explained
Third grade/ numbers and operations/ represent numbers on a number line/ I would use this to solidify the connection between adding numbers and representing them on a number line
Open Number Lines: Task Cards The Common Core standards call for students to use number line strategies flexibly and efficiently.
Open Number Lines Activities ($) Easily guide your students through this Common Core math strategy that will help them master addition and subtraction with and without regrouping