Is science a religion? That’s basically a philosophical question, and like most philosophical question it unfortunately devolves into linguistics and epistemology.
Different people have different mental images in their minds when they use a certain word. For an atheist, the word “religion” conjures up the image of belief in a magical being who directly and deliberately influences the world, and perhaps who has followers in organized churches. But for one of those believers, the word “religion” might simply denote a particular world view. Your “religion” is how you view the world, regardless of what you think (or do not think) is the prime mover in the universe. So to some christians, atheism is a religion, and science is a religion.
Remember when this discussion comes up that it is about the definition of words, and words like “faith” have multiple definitions, and personal interpretations vary. In fact there is so much variation in these definitions and interpretation that it makes the argument around “is science a religion” rather fruitless. Best to avoid it.
Best really, to focus on what science IS, and to describe it in less ambiguous terms. Science is a system of discovering how the universe appears to work. A method of making predictions that can be tested. A system that is by its very nature always uncertain to varying degrees. A systems that is in constant flux. Not a set of fixed beliefs, but a way of finding out what seems to be the best explanation for what we observe, and a way of always allowing new explanations to be considered when new observations come along.
Something like this:
Uncinus's Science Blog 