I hate wordsearches where all the words are given, especially in Maths. What are they learning? What I do like to do is create puzzles, like this one, where a mathematical skill is required to generate the values that need to be found in the puzzle.
One sequence seems to repeat, make sure you find both of them otherwise the code doesn't quite work out right.
This takes almost a full lesson.
A nice number search activity where students are required to find sequences of numbers rather than words. Students must apply their skills of generating a sequence from an nth term rule. This is an excellent way to consolidate a lesson, or series of lessons on this topic. Once the students have found all of the sequences, there is a code to break which forms an extra challenge.