Math requires practice! Anything that can add variety and encourage the children to put in some practice time, will help them be more successful at math.
This set includes eight *differentiated* mystery picture puzzles on the hundreds chart: there are two different pictures, and for each picture there are four levels to choose from.
In the basic puzzles, the numbers are given as sums of tens and ones (expanded notation). In the next level, the students are asked to compute +1, -1, +10 or -10 of a number on the hundreds chart. The intermediate puzzles contain simple sums and differences within 100: either adding/subtracting within the same ten or adding/subtracting whole tens. The advanced puzzles contain more general additions and subtractions of two-digit numbers and they are designed to develop mental math skills.
I marked the worksheets with one, two, three or four elephant symbols, depending on the skills required, to make it easy to pick the right level.