Phase:  After/Explain/Elaborate 
Activity: 

Assessment Strategies:  The teacher will observe the students while they play the game. The teacher can use the following questions to guide his/her assessment of student progress toward mastering the standards:

Advanced Preparation: 

Variation Tips (optional): 

Notes or Recommendations (optional):  ALCOS 2019 Mathematics Standards: 1. Use addition and subtraction to solve word problems within 20 by using concrete objects, drawings, and equations with a symbol for the unknown number to represent the problem. 2. Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20 by using concrete objects, drawings, or equations with a symbol for the unknown number to represent the problem. 4. Explain subtraction as an unknownaddend problem. 8. Solve for the unknown whole number in various positions in an addition or subtraction equation, relating three whole numbers that would make it true. 
Keywords and Search Tags:  addition, difference, missing addends, numbers, online game, problem solving, relations between numbers, strategies, subtraction, unknown addends, word problem 