  The electromagnetic and axial form factors of the nucleon and its lowest
positive parity excitations, the Delta(1232) and the N*(1440), are calculated
with constituent-quark models that are specified by simple algebraic
representations of the mass-operator eigenstates. Poincar\'e covariant current
operators are generated by the dynamics from single-quark currents that are
covariant under a kinematic subgroup. The dependence of the calculated form
factors on the choice of kinematics and on the gross features of the wave
functions is illustrated for instant-form, point-form, and front-form
kinematics. A simple algebraic form of the orbital ground state wave function,
which depends on two parameters, allows a fair description of all the form
factors over the empirically accessible range, although with widely different
choices of the parameters, which determine the range and shape of the orbital
wave function. The neutron electric form factor requires additional features,
for instance the presence of mixed symmetry S-state component with 1 -- 2 %
probability in the ground state wave function. Instant and front form
kinematics demand a spatially extended wave function, whereas in point form
kinematics the form factors may be described with a quite compact wave
function.
