Build students' number sense with 2 & 3 digit numbers with these Number Sense Brain Teaser task cards. These rigorous and engaging math task cards are perfect fast finisher activities for 1st and 2nd grades. Students are given clues on how to solve the missing numbers using logical reasoning, addition, and/or subtraction, helping to build students' critical thinking, mental math skills and number sense.WHAT'S INCLUDED:• 40 brain teasers task cards• optional number tiles in color or black and