Mini and Medium Plinko (Galton Board, Binomial Distribution, Bernoulli Trials)

Mini and Medium-Sized Plinko Boards, Using Marbles of up to 16mm in diameter.

Two layers and three layers, designed for students to develop insight into the plinko binomial distribution in a differentiated way.

In the case of a two-layer plinko, how is it related to the problem of "flipping two coins and getting a head and a tail? In the case of a three-layer plinko, how is it related to the problem of "flipping three coins and getting two heads and a tail?

A four-layer version is here: https://www.thingiverse.com/thing:2747357

Please educate young children not to put small parts in their mouth and do encourage them to ask questions about mathematics. Have fun playing with probability!