Ace the 2026 MTTC Upper Elementary Literacy Test (122) – Ignite Your Teaching Passion!

Distinguishing the main idea from supporting details means finding the one central point the author wants you to take away and then seeing how the other sentences back that point up with evidence, examples, or reasons. The main idea is the core claim or message, while the supporting details build it up and show why it’s true or important.

To locate them, look at the sentences that express the big claim or purpose of the text—often these are hinted in the topic sentences of paragraphs and reinforced by information that repeats or echoes a shared idea across sections. When you notice ideas or facts that keep returning to the same point, those details are helping to develop the main idea rather than standing on their own as the message.

That’s why the described approach is best: the main idea is the central point; supporting details are the evidence and examples that develop it. You might find the central message stated explicitly in topic sentences or implied through patterns of repetition and emphasis throughout the text. The other statements don’t reliably describe how main ideas and details work or how to locate them.