  Classical scale invariance (CSI) may be one of the solutions for the
hierarchy problem. Realistic models for electroweak symmetry breaking based on
CSI require extended scalar sectors without mass terms, and the electroweak
symmetry is broken dynamically at the quantum level by the Coleman-Weinberg
mechanism. We discuss discriminative features of these models. First, using the
experimental value of the mass of the discovered Higgs boson $h(125)$, we
obtain an upper bound on the mass of the lightest additional scalar boson (~543
GeV), which does not depend on its isospin and hypercharge. Second, a
discriminative prediction on the Higgs-photon-photon coupling is given as a
function of the number of charged scalar bosons, by which we can narrow down
possible models using current and future data for the di-photon decay of
$h(125)$. Finally, for the triple Higgs boson coupling a large deviation (~ +70
%) from the SM prediction is universally predicted, which is independent of
masses, quantum numbers and even the number of additional scalars. These models
based on CSI can be well tested at LHC Run II and at future lepton colliders.
