This lesson introduces learners to key evidence used in modern cosmology. It links observations of distant quasars, the Cosmic Microwave Background and gravitational effects to current models of the Universe, including dark matter, dark energy and possible long-term outcomes. Use the starter to identify prior understanding, then teach each main section through short explanations, diagrams and paired discussion. Emphasise the evidence chain—observation, scientific problem, proposed explanation and supporting evidence—and regularly check that learners can distinguish dark matter from dark energy. The plenary provides a quick assessment of core knowledge, while the follow-up tasks can be used for independent practice or homework.