Mental computation helps students build on number relationships rather than memorization procedures to solve problems. This set of task cards focuses on students ability to “make tens” to solve addition problems mentally. Students look for numbers within an equation to create groups of ten.
Example: 2 + 5 + 8
2 + 8 =10 10 + 5= 15
*In this example students would add 2 + 8 to create a group of ten. Students then add 10 + 5 to complete the equation.
Example: 6 + 8 (think: 4 + 4 = 8)
6 + 4 = 10 10 + 4 = 14
*In this example students would decompose 8 to 4 & 4, because of the 6 in the equation. Students create a group of tens by adding 6 + 4, and then 10 + 4 to solve the equation.
Ways to use the these Task Cards (18 included):
Collaborative Pairs-partners take turns solving problems mentally
Math Center-students record answers on sheet provided
Quiz-Quiz-Trade-Give each student a card. Students mentally solve the problem, quiz a classmate on their card and trade cards. Students continue quizzing each other and trading cards until teacher says stop.