How do you lock elements in a Powerpoint page so they cant be moved?

I don't know what you mean by the undefined "think this." Not being clairvoyant is a fault that I freely admit to. I didn't realize not being clairvoyant makes me a stupid person.

The reality is the PowerPoint simply does not have the feature you are asking for, and that using Themes is currently the best you can do.

There is a suggestion forum that is read by and responded to by Microsoft. This topic exists, but at the moment it has only 10 votes, which suggests to Microsoft that this is not an important issue. You can boost the suggestion by voting for it here:

Locking place, size of text boxes should available, as well as locked font attributes.

In PowerPoint for Windows, this does not appear to be a hot topic. Here's the topic in the Windows forum:

Lock placeholder and other objects to prevent modification

Please don't be too hard on those who are simply stating facts and offering suggestions on how to make the best of the situation as it exists.

Do you have anything to contribute to this discussion?

Or are you just here to hurl abuse at the volunteers who are trying to help solve another user's problem?  Let me emphasize that:  *volunteers*, NOT Microsoft employees, though rudeness is rudeness, no matter at whom it's directed.

I think you are really stupid if you think this. The main reason why people (especially designers) have to suffer using this awful application, is to give clients (who usually don´t know how to deal with that stuff) a presentation that they later can modify. And most of the times there are layout elements that have to be locked to prevent that those user accidentally move them. 

But I´m sure you are a Microsoft addicted and like all of them you don´t even understand the most simple things that users encounters in the everyday workflow. That´s why Microsoft application are so stupid, awful and absolutely unusfyl designwise !!!!

As Jim points out, learning how to work with themes will be very helpful. 

At root, though, unless you can get your team members to cooperate on a set of standards (theme, template in use, presentation aspect ratio), the problems you describe won't go away.

If everyone standardizes on the same theme and the same slide size and a short list of fonts to use when it's necessary to choose non-theme fonts, most of the problems you describe will go away.

Incidentally, if you need more information on this topic, visit Echo Swinford's site, www.echosvoice.com

She and Julie Terberg (www.terbergdesign.com) have written THE book on creating templates/themes for corporate/branding purposes. 

Building PowerPoint Templates - Step by Step with the Experts

Full disclosure: Both of the authors are friends and colleagues, both are PowerPoint MVPs, as am I, but I've no financial interest in the book.  Other than the fact that I've already bought two of them.  One real book, one for the e-reader.