Topics: what an equation is · the meaning of “=” · claims that can be tested

A box of unknown weight sits on a balanced scale — and that picture is the whole idea: an equation is a CLAIM that two sides are worth the same. Students learn to read “=” as a promise, not a “here comes the answer” signal, and test their first claims by eye.

New law: A shape hides a number. Same shape — same number. / The sign “=” means: both sides are worth the SAME.

The check: ten questions below — the case closes at 80%. Not there yet? A detective reopens a case as many times as it takes; every pass turns up new evidence.