In my experience...
In previous seasons, we have tried showing the kids how to take their steps, where there plant foot should land, how to take the first step, etc...never worked out very well...the boys were thinking instead of kicking...
Lot's of kids now days have played soccer (at least here in Texas)...and when they play soccer, they don't measure their steps, they don't worry about how the plant, they just run up to it and kick it...
So this season, we put the ball on the tee for the boys to kick...and if they asked how to kick it we said, just kick it...we had 3 or 4 boys who kicked it well, so we looked at them some more off the tee and off the extra point block, telling them to just kick it....one stood out above the rest as far as consistency went...the only thing we had to fix was telling him to keep his eye on the ball...