Q: How to best repurpose older MacBook for my teenage daughter

What to do before selling or giving away your Mac - Apple Support

Before Selling or Giving Away Your Pre-Lion Mac

Follow these instructions until you get to Step 5:

https://support.apple.com/en-us/HT201065     What to do before selling or giving away your Mac - Apple Support

When you reach Step 5 you will need your Snow Leopard or earlier installer disc that came with the computer when it was new.

1. Follow these steps for installing the original version of OS  that came with the computer.

     1. Boot the computer using the Snow Leopard Installer Disc or the Disc 1 that came

         with your computer.  Insert the disc into the optical drive and restart the computer.

         After the chime press and hold down the  "C" key.  Release the key when you see

         a small spinning gear appear below the dark gray Apple logo.

     2. After the installer loads select your language and click on the Continue

         button. When the menu bar appears select Disk Utility from the Utilities menu.

         After Disk Utility loads select the hard drive entry from the left side list (mfgr.'s ID and

         drive size.)  Click on the Partition tab in the DU main window.  Set the number of

         partitions to one (1) from the Partitions drop down menu, click on Options button

         and select GUID, click on OK, then set the format type to MacOS Extended

         (Journaled), then click on the Apply button.

     3. When the formatting has completed quit DU and return to the installer.  Proceed

         with the OS X installation and follow the directions included with the installer.

     4. If you are planning to sell or give your computer away, then do the following:

        After you reformat your hard drive and reinstall OS X, the computer restarts to a

        Welcome screen and asks you to choose a country or region. If you want to leave

        the Mac in an out-of-box state, don't continue with the setup of your system. Instead,

        press Command-Q to shut down the Mac. When the new owner turns on the Mac,

        the Setup Assistant will guide them through the setup process.

You can order replacement discs from Apple.

Apple Store Customer Service at 1-800-676-2775 or visit online Help for more information.

To contact product and tech support: Contacting Apple for support and service - this includes

international calling numbers..

For Mac App Store: Apple - Support - Mac App Store.

For iTunes: Apple - Support - iTunes.

If your computer came with 10.6.2 or earlier, then you can:

Upgrading to Snow Leopard

You can purchase Snow Leopard through the Apple Store: Mac OS X 10.6 Snow Leopard - Apple Store (U.S.). The price is $19.99 plus tax. You will be sent physical media by mail after placing your order.

After you install Snow Leopard you will have to download and install the Mac OS X 10.6.8 Update Combo v1.1 to update Snow Leopard to 10.6.8 and give you access to the App Store. Access to the App Store enables you to download Mavericks if your computer meets the requirements.

     Snow Leopard General Requirements

       1. Mac computer with an Intel processor

       2. 1GB of memory

       3. 5GB of available disk space

       4. DVD drive for installation

       5. Some features require a compatible Internet service provider;

           fees may apply.

       6. Some features require Apple’s iCloud services; fees and

           terms apply.

I cannot help you with the Office software. If you legally own it, then you should have the serial number should you reinstall it. However, you will need the Office disc because you cannot download older versions of Office from MS. If you have lost your disc and/or forgot the serial number, then you need to call MS Support for the serial number.

You may or may not have luck in getting a replacement battery at an Apple Store. Apple only provides hardware support for machines for 5 years. After that time they tend not to have parts (like going to a dealership for car parts after a car is older than 20 years).  You may find it less expensive and easier to turn to a third party supplier. Be careful with batteries though because some really cheap ones are junk.  If you are uncertain about this kind of thing a good starting place is OWC mac-sales.com which specializes in Mac parts.

Link for Limnos' answer.

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