I found that my problem was unclear instruction about the timing between jumping and popping. One day when I was watching a slowmo ollie video though, I noticed that the skateboarder already was beginning to jump (at least his body was already going in an upward motion) before snapping the board off the ground. That was a critical change I needed to make in order to get it working. I had been trying to pop the board while all my weight was still pushing down on it (kind of an obvious mistake, but I somehow overlooked this). Hope this helps somebody.
The ollie is a fundamental trick in street skateboarding, and is used to leap onto, over, or off obstacles, or over gaps of unfriendly terrain such as grass or stairs. As so many other tricks depend on it - for example the kickflip and heelflip - the ollie is often the first trick to be learned by a new skateboarder. The ollie typically takes considerable practice to learn.

The Rimable Complete 22″ Skateboard is the most compact street board that are ready-to-use.  It is best for exercise and fun, and very portable.  There are five colors that you can choose from Black, Blue, White, Purple, and Green.  It has high-quality construction, with a high-density plastic deck.  It features extremely smooth 59mm wheels along with ABEC7 bearings and solid aluminum trucks.  It measures 22″ long and 6″ wide and weighs 4 pounds.  It has the best rating of 4.3 on Amazon.

Smile and wave – Feel free to look around at all the other people at the skatepark that stood by and marveled at your new-found accomplishments (all one of them). I’m sure by this point you’ll be picking up roses that are being thrown at your feet, and taking a well-deserved bow as they begin to chant your name. Take it all in, thank the crowd for their undying affection, and then go get a snow-cone. You deserve it, champ.