When students are first learning about semiconductor devices, and are most likely to damage them by making improper connections in their circuits, I recommend they experiment with large, high-wattage components (1N4001 rectifying diodes, TO-220 or TO-3 case power transistors, etc.), and using dry-cell battery power sources rather than a benchtop power supply.
If there are any substantial errors (greater than a few percent), carefully check your circuit’s construction against the diagram, then carefully re-calculate the values and re-measure.Carefully measure all voltages and currents, to verify the accuracy of your analysis.Mathematically analyze the circuit, solving for all voltage and current values.Check the accuracy of the circuit’s construction, following each wire to each connection point, and verifying these elements one-by-one on the diagram.Carefully build this circuit on a breadboard or other convenient medium.Draw the schematic diagram for the circuit to be analyzed.Carefully measure and record all component values prior to circuit construction, choosing resistor values high enough to make damage to any active components unlikely.For successful circuit-building exercises, follow these steps: You will learn much more by actually building and analyzing real circuits, letting your test equipment provide the “answers” instead of a book or another person. While this is good, there is a much better way. Typically, students practice by working through lots of sample problems and checking their answers against those provided by the textbook or the instructor. Learning to mathematically analyze circuits requires much study and practice.