The eLibrary search is designed to be simple to use and offer you a good range of results. You can look for resources by either browsing complete collections, or searching using particular key words.

Materials in the eLibrary are usually grouped as collections. A collection may be:

• materials from particular projects, for example, cre8te maths, a discrete curriculum and CPD project (http://stem.org.uk/cx3y)
• resources provided by a particular organisation, for example, the Association of British Pharmaceutical Industry (http://stem.org.uk/cx4o)

You can browse all the collections in the eLibrary by selecting the 'Explore' option.

If you prefer to look for resources by key term, use the eLibrary 'Search' option.

• As you enter a search term the eLibrary uses pre-emptive suggestions, which are based on previous search terms conducted by eLibrary visitors.
• The search engine compares your key term(s) to the eLibrary resources and returns a list of search results by relevance.
• You can change the order of search results at any time by selecting an alternative priority from the drop-down 'Sort by' menu - for example alphabetically, by popularity, and by publication year.
• Resources may also be flagged to give you additional information, for example, 'New' resources have been added in the last week, 'Most popular' are those in your results list that have been viewed the most, and 'Archive' resources were published prior to 1990.

At any time you may refine your eLibrary search by using the filter options on the left-hand side of the page. For example, you may wish to narrow a search by:

• subject
• age range, key stage, or Scottish level
• type of resource (such as experiment, video, interactive, teacher guidance)
• publication year
• publisher

When you use one or more key words to search for a resource, the following information is checked:

• resource title
• resource description
• for print materials, a full-text search of the resource
• key words added to the resource metadata (tags)

Very common words, such as 'the', 'and', are ignored for searching.

The resources that appear at the top of your search results list contain exact matches to your search term. Further down your results list you may see a break with the heading 'The following results are only a partial match to your search terms'. Resources listed after this point contain some of your search. For example, a search for 'trapping carbon dioxide' returns two resources with the exact search term, and 395 resources containing one or two of the terms 'trapping', 'carbon dioxide' or 'carbon'.

Results are by default prioritised by relevance, which is determined by the number of times your search term appears, and also where - terms appearing in a resource title have more weighting than terms appearing in, for example, a Word document that forms part of the resource.You can change the order of search results at any time by selecting an alternative priority from the drop-down 'Sort by' menu.

Once you have performed a search the quickest way to refine your requirements is to use the filters on the left-hand side of the page. For example, if you were looking for an interactive algebra resource for students aged 11-14, you might begin with the general search term 'algebra', and then filter the results by age and resource type.

As you apply each filter the eLibrary dynamically recalculates the number of resources in each category, and updates the information provided to you. This means that the filters only indicate categories where relevant resources are available.

The eLibrary search by default looks for exact matches to your search term, so it is not usually necessary to use Boolean operators to refine your search. However, you may occasionally wish to use quotation marks around a particular phrase within a search term. For example, searching for ' "genetic engineering" crops' would indicate that you are interested in resources that reference genetic engineering specifically with respect to crops

Once you have registered with the eLibrary you may receive periodical Newsletters to keep you up to date with new resources in the eLibrary. These updates will be tailored to your particular areas of interest.

If you would like to receive more immediate updates when new resources are added to the eLibrary then you may subscribe to a Webfeed.

Webfeeds let you know when websites have added new content. The National STEM Centre site uses feeds in two ways:

• To provide a News feed of all the stories added to our News pages.
• To provide customisable feeds of resource updates. For example, you can subscribe to a feed for the whole site, which will alert you to all new resources or collections. Alternatively you may prefer to be alerted when new resources are added to one subject area, or to a particular search that you have done.

Wherever you see the orange RSS icon on the site you can subscribe to a particular feed. When you hover over the icon the content of that particular feed will be displayed.

The way in which your computer stores and displays feeds depends on individual computer settings. More information on using feeds is available from the BBC. To make use of Webfeeds you will need a 'RSS reader', also knows as a 'RSS aggregator'. If you are unfamiliar with using RSS feeds we suggest you speak to your school or college technical support. Alternatively, as a starting point it may be helpful to know that email programmes can act as RSS readers. For example, if you use Outlook as your email programme you can display Webfeeds in an email folder.