Build problem solving mastery through explicit practice with part-part-whole problem types! These 20 digital, no prep story problems practice adding 3 numbers within 20 in put together problem types presented in the standards. Students use the built in tools to write equations, and build models on tens frames and number lines using the built-in, movable manipulatives before solving. WHAT'S INCLUDED • 20 Adding 3 Numbers Word Problems (part-part-part-whole) • Printable recording sheets