Tri This Math app for iPhone and iPad

Need to practice the four basic arithmetic operations? Need to practice creating number sentences with three numerals? Need to practice using 3 addends for sums to 20? Need to practice mixed operation number sentences with totals to 99?

In each turn players are given four numerals. Each player has five turns. Use three of the four numerals and the basic arithmetic operations (+, -, x, ÷) to form an equation that equals any empty square (or one occupied by your opponent) on the game grid.

The total for each number sentence is computed using standard order of operations.... multiply and divide (left to right) then add and subtract (left to right). Drag that total to the corresponding grid square. Your accumulated point total for each match is updated after each term and is the total of all the grid squares you occupy plus any BONUS points earned.

You may not use an answer grid square you occupy, but you can ‘steal’ your opponent’s square. In that case, your score increases and your opponent’s score decreases by the same amount.

Grid size options include 20, 25, or 50 squares. The numeric range for the grids includes 14 options: 1-20; 11-30; 1-25; 15-29; 1-50; 50-99 and others.

Some Common Core connections:
Add and subtract within 20.
CCSS.MATH.CONTENT.1.OA.C.5
CCSS.MATH.CONTENT.2.OA.B.2

Multiply and divide within 100.
CCSS.MATH.CONTENT.3.OA.C.7

Solve problems involving the four operations...
CCSS.MATH.CONTENT.3.OA.D.8
CCSS.MATH.CONTENT.4.OA.A.1