Mull

We prefer Smidge the midge also amazon. Works for us better than avon.

Mull is a lovely island, even with man-(and woman-)eating midges. Whale and dolphin watching trips can be arranged from Tobermory. The museum in Tobermory is run entirely by volunteers and is worth a visit there are exhibits from a Spanish Galleon from the Armanda which was wrecked off Tobermory and is now a magnet for divers, though I don't think that's in your plans, Greenfinch . The local bookshop has plenty of locally produced booklets which will tell you all you need to know - and more. There's a magnificent beach at Calgary which I'm sure would be ideal for the twins. Crossed fingers for good weather.

Oh you will really need insect repellent scottish midges are B*****S it is alleged the the SAS use skin so soft.

www.amazon.co.uk/Avon-Guard-IR3535-EXPEDITION-Spray/dp/B00199RQ5S

You might want to try a midge face cover as well.

www.survivalaids.com/british-forces-mosquitomidge-micro-head-net?gclid=CJit0oTRiMcCFdMatAodaYYK0Qio

Trip out to iona and Fingals cave is a brilliant. Also boat out to see the seals. ISpy books are a joy for travelling. Really loved Iona and met someone who had gone on a retreat there every year for over 20 years. I met her drinking champagne in Glasgow. I decided I wanted to do the same( she was in her eighties) caveat the weather was brilliant.

If the wee ones are familiar with the Balamory tv programme then visit Tobermory. My Dgd's had a super time identifying the coloured houses which are home to the various tv characters.
Torosay castle is exploration territory!
And yes to midge repellant. (Midges are definitely a west coast problem!)

I've never been to Mull but if it's like a lot of Scotland you will need to protect yourselves from midges.

You could prepare them a discoverer's backpack each containing a cheap pair of binoculars, a bug catcher, a magnifying glass, a pen/pencil and a homemade little booklet of things to find/see? Make some easy and some harder. Children love minibeast hunts so you could put some bugs in the booklet. If you are going to be near a pond you could also put some pond life in it and go dipping.

They could also make a memory stick. Each child has a stoutish stick...they have to find it on day one if possible...a bit like a walking stick. Wrap lots of rubber bands around it. The children fasten things they find such as feathers, leaves or anything that interests them to the stick using the rubber bands. Once home they can stand them in the garden like totem poles. to remind them of where they went and what they saw.