Object states and the timeline

Judy, of course, gave you the solution, but for anybody that reads this, perhaps I can shed a little light on why it didn’t work for you originally.

You said,

What should happen is at the eight-second point the slide pauses, and the learner clicks “Pick sodium” and the trigger changes the state of “Water plush” to hidden and resumes the timeline.  At 20 seconds the sodium plush should be shown since that’s where it first enters the stage on the timeline.

What’s actually happening is the water plush isn’t changing state and appears at the 20 second point (it’s overtop of the sodium plush).

When an object appears later on the timeline, it isn’t non-existent, as most people assume. It is present, but in a temporary hidden state. The appearance point on the timeline has a built-in trigger to change the state to Normal. So your trigger to change “water plush” to the hidden state has no effect. Then when the timeline reaches 20 seconds, it changes “water plush” from Hidden to Normal, as it is designed to do.

I’ve tried having both plushies initial state as hidden and using the team selection to change the appropriate ones state to normal, but that makes it appear immediately instead of at the 20 second point where is starts on the timeline.

That also means you can’t change the state of an object, and expect it to stay hidden until the timeline shows it, and have it show up in that state. When your trigger changes its state, it leaves the Hidden state and assumes the new state immediately.