How do you effectively steer a user OFF your site and onto another one?

Question

I'm working with a client who has a network of websites, each with content that will appeal to a specific audience. The issue we're having is that the client's flagship site will, for the foreseeable future, continue to receive visitors who are looking for the content earmarked for one of the client's OTHER sites.

As an example, imagine that the client is named Awesome Schools, and their flagship site awesomeschools.com has content that is about creating and nurturing awesome schools (it'd appeal to education policy makers, school administrators, etc), while their sister site awesometeachers.com has the content more likely to appeal to teachers (lesson plans, testimonials from other teachers, networking opportunities for teachers, etc.).

What is a good method for effectively getting teachers over to awesometeachers.com when they visit awesomeschools.com?

We're trying to avoid audience-based navigation within awesomeschools.com in favor of content-based navigation because while we're comfortable drawing a sharp line between practical content FOR educators and content ABOUT education (and having separate websites for the two audiences), we really don't want to be drawing lines that rigid within each site - we don't think those lines exist quite as rigidly once you get down below the site-to-site level.

Answer 1

Instead of pushing teachers to another site - why not pull them there instead? Post a big informative link that attracts teachers:

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Answer 2

Here are a few examples of sites connecting to related sites or subsites. In all but one, there is no description of the purpose of the other sites. Perhaps the site owners assume their visitors know which site is best suited for their needs.

I've listed them in decreasing order of prominence of the navigation to the other sites.

Gap
The Gap owns Gap, Old Navy, Banana Republic, Piperline, and Athleta. These brands target somewhat unique audiences. Navigation between these sites is through microsites on gap.com.

Newsobserver.com
Similar to gap.com, links to other sites appear at the top of the page. I do not know how well this works though. This paper is one of many owned by McClatchy interactive. McClatchy seems to be standardizing their site layout and newsobserver.com is not their standard layout.

Backcountry.com
Backcountry's outlet store is Department of Goods. The link to the outlet appears at the end of the main navigation bar on backcountry.com. A description of Department of Goods, somewhat like the answer above suggests, appears on mouseover on the link to the site.

Microsoft
The sites for Windows Phone, Xbox, and Skype are separate sites from Microsoft's main site. Links to those sites appear twice on Microsoft's home page.

Dell
Dell makes Alienware computers and selles them on a separate site. The link to the Alienware site is in the For Home menu.

Stack Exchange
The links to the other sites appear at the bottom of the page.

Except for gap.com and newsobserver.com, the main sites include links to the child sites but the reverse is not true.