A dodgeball variant. Use one or two large/ish (volleyball or football sized) balls. The softer the ball the slower it is and easier to dodge and better for young children, but I’ve found that older children prefer playing with a faster, harder ball which requires more skill to dodge, such as a cheap football (UK football/soccer).
One or two players become the ‘taggers’ and using the ball they have to tag the other players by hitting them below the knee with the ball. In ‘Butt-in-the-way’ players can either dodge the ball as normal or can use their butt to block the ball coming at them. However, if the ball hits them below the knees while attempting to block the ball, they are still out.