Multifunctional teaching ruler

The utility model relates to the field of teaching, in particular to a multifunctional teaching ruler, which is provided with a compasses telescopic arm and a telescopic scale, circles of different specifications can be drawn conveniently through the cooperative use of the compasses telescopic arm and the telescopic scale, and a plurality of objects can be measured through the telescopic scale. The telescopic ruler can change the measurement range and comprises a shell, a compasses telescopic arm and a telescopic ruler body, the two hinge rings I and the two hinge rings II can facilitate hinged connection of the fixed shell I and the fixed shell II through the two hinge columns, and the fixed shell I is not disengaged from the fixed shell II. The semicircular boss is hinged to the fixed shell I and the fixed shell II through the two hinge columns, the semicircular boss can rotate around the hinge columns, and the compasses telescopic rod can rotate around the hinge columns through thesemicircular boss. And th