you should learn to do standing and sitting jumps (sprints out of and in the saddle).

the rear wheel is popping up because you are pulling hard on the upstroke, but have not yet made your opposite pedal stroke efficient.

In short - you need to worry more about form versus speed at this juncture. Picture your EACH of feet making its own perfect fluid circle as it moves through the full pedal stroke. Every stroke. Everytime you pedal.

in time, it will happen without thinking about.
that is pedaling efficiency