A game I made up for my students to not only practice the underhand throw, but some communication/teamwork.
Basically they have to underhand throw beanbags from one “island” to a bucket on one of the opposing teams islands. The third island is where the beanbags start. There is only one path to/from the different islands and only one person may pass at a time. Students may also only transport one beanbag at a time. At the end of the time limit the team with the most beanbags in the opposing teams bucket wins. an image of the setup is attached above. It worked well with my classes (smaller) and could be adapted to larger classes.