Observe and adjust
Experience small achievements repeatedly
When "observation" begins

When you make a zigzag and start playing, you will start observing the rolling marbles. I'm sure you don't mean to "observe". If the marbles stick out of the rail, the adjustment will start by changing the position or angle of the rail. "Adjusting" is probably a natural feeling. You may be able to help a little at first. By making it easy to put on and take off with a magnet, "observation" and "adjustment" will blend into the play.

If it's too slow
Does not roll
If it's too fast
Will pop out
It is a very simple mechanism that the ball rolls toward the bottom of the slope. It's easy to start playing just by seeing it passing by at an event. It is not effort that is required to experience a small achievement. Observe while playing and enjoy the adjustment.
Small achievements go beyond easy "adjustment"
The rolling appearance of marbles has a charm that even adults will want to repeat.
It has the charm of rolling marbles and the ease of handling magnets. The stress-free ease of handling of magnets, which is easy to move from imagination to execution, immediately responds to the independence that you want to try. Even if you make a mistake, the cause is very simple. It is easier to exert the power of observation naturally. Even when adjustment is required, it can be easily arranged with a magnet type.
The attraction of rolling marbles that you naturally want to repeat is the driving force that repeats the cycle of "imagination-> execution-> observation-> adjustment" while playing.
It is a toy that can be played naturally by using its independence, observing power, and adjusting power.
Observe the current situation and adjust to the successes and goals you envision. If the process is fun, I think it's a useful feeling.