I know I should not be as excited as I am at working through the equivalencies insets. But they are really hard to make out of poster board. Montessori materials are so precise. Darn that need for exactitude.
One of the disadvantages of teaching at home is the need to purchase only what I can’t make as far as materials go. So, that left us with no beautiful metal insets to study the beginnings of Euclidean geometry and lay the foundations for theorems. Eight presentations with 12 or so paper insets. That came after the triangle boxes had to be traced and made into papers for the visual only discussion of the topic. Plus the extensions for the boxes require tracing the tracings. Agggggggg. Breathing again.
Triangles are equivalent when their bases are equal and their altitudes are equal.