<p>In this article, the scaled consensus is considered for high-order nonlinear multi-agent systems (MASs) within a prescribed-time. First of all, recognizing that only a subset of followers can access the leader’s state, we develop a prescribed-time distributed observer that employs time-varying scaling functions and scaled factors. By utilizing the backstepping method, it is rigorously prove that the states between the leader and observer can achieve scaled consensus within a prescribed-time interval. Moreover, by developing an innovative coordinate transformation scheme, a distributed control protocol is designed to ensure the prescribed-time leader-following scaled consensus. To further optimize the algorithm and minimize communication frequency, an event-triggered control protocol is proposed, in which the triggering function comprises a time-varying variable. Employing the theory of prescribed-time stability, some sufficient conditions are derived for achieving scaled consensus within a prescribed-time. Finally, several numerical simulations are given to validate the effectiveness of the proposed prescribed-time distributed observer and control protocols.</p>