# Unit 7: Addition, Subtraction, and the Number System (Part 4)

Independent

Games & Activities:

Worksheets:

Videos:

PS11Showme Videos:

Online Games (Websites & Apps):

Apps:

Family

Games & Activities:

• Teach a family member how to play ten plus any two digit number.
• Use the members of your family to create a story problem about a problem you had that day
• Play with a family member the card game “War.”
• Create a Tic Tac Toe board with a two digit addition or subtraction equation in each box. In order to put your “X” or “O” you must solve the problem and have your partner check your work.
• Teach a family member an addition or subtraction strategy (Expanded Form, Base 10 Sketch, Open Number Line, Keep One Break One). Then give them a list of problems to solve. Check their work!

Projects:

• A student subtracts a 2-digit number from a 2-digit number and says the difference is 20. Both the 2-digit numbers end in zero. What might the two numbers be?

Extension

• Solve a two digit addition or subtraction problems using as many strategies as you can! Create a poster to share your strategies.  Can you use all four?
• Expanded Form
• Base 10 Sketch
• Open Number Line
• Keep One Break One

Reflect: Which strategy was the most efficient strategy to use?