Thermoresponsive linear polymers and their corresponding aggregates or nanogels typically show similar thermoresponsive profiles. In this study, the authors demonstrate reversible chemical switching between linear polymers and their cross-linked nanogels. The linear polymers exhibit sharp thermal transitions typical of common thermoresponsive polymers but the cross-linked nanogels exhibit "linear" thermal transitions over a relatively broad temperature range. The reversible switching between these two different polymer architectures with distinct thermoresponses represents a unique example of how the responsive properties of smart polymers can be significantly manipulated via polymer architecture engineering.