
With the free Formulator Tarsia software from Hermitech Laboratory, it is possible to create puzzles, domino activities and rectangular card sorts. These work well with students of any age. Most of the published resources seem to be for students age 11 to 18 but as it is possible to create puzzles, teachers of younger students could create puzzles suitable for their classes.
The software can be downloaded from this link. Scroll down to the section headed Formulator Tarsia.

Note that as well as downloading the application it is possible to download selections of puzzles from Craig Barton and from Bryan Dye. Craig also has a section of his website devoted to Tarsia – note all the ideas here for using Tarsia in the classroom.
Further puzzles can be found on M Ladak’s MathedUp site (see the KS3 and KS4 pages for resources) and numerous resources from Mark McCourt’s Emaths site.
TES Resources host an extensive collection of Tarsia Puzzles.