What's the sport similar to volleyball but you kick the ball instead?

It could be one of these.

Footvolley.

Footvolley is an entirely new sport which combines beach volleyball and soccer skills where the difference is that the players may not contact the ball with their hands or arms; instead they can use all other body parts including their feet, head and chest, etc. Sport originated in Brazil; but is quickly becoming popular in the US, Europe, and Asia.

Sepak Takraw

Sepak Takraw is a variant of volleyball popular in Asia, similar to Footvolley. The rules are very similar to those in volleyball, with the following four important exceptions: The use of hands is not permitted, each player may only touch the ball once before it is kicked back over the net, there is no rotation in the defence position and players use their feet to get the ball over the net. The game is played on a badminton doubles court. Another similar game played with the feet and originating in Thailand is Buka Ball.

Footbag Net

Footbag Net is similar to sepak Takraw and Footvolley. It's played with feet instead of hands. Footbag Net combines elements of tennis, badminton, and volleyball. Specifically, the court dimensions and layout are similar to those of badminton; the scoring is similar to the old scoring system in volleyball (you must be serving to score); and serves must be diagonal, as in tennis. It is played one on one or in teams of two. Footbag Net games can be played to eleven or fifteen points, although the winners must win by at least two points.

In high school, it is illegal to contact the ball with any part of the body below the waist. In club volleyball, anything goes, as long as you don't hold the ball in any way. Usually refs will let it go if it just bounces off of your foot, but kicking it intentionally is usually a point for the other team. It is also a yellow card in high school. Short answer: yes, but only in club. In high school volleyball you cannot.

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