usborne do a good summer sticker book !!!
http://www.amazon.co.uk/Summer-Stick...7373046&sr=1-2 (http://www.amazon.co.uk/gp/product/1409524752/ref=as_li_ss_tl?ie=UTF8&tag=childminding-21&linkCode=as2&camp=1634&creative=19450&creativeASIN=1409524752">1000 Summer Stickers (Usborne Sticker Books)</a><img src="http://www.assoc-amazon.co.uk/e/ir?t=&l=as2&o=2&a=1409524752" width="1" height="1" border="0" alt="" style="border:none !important; margin:0px !important;)
or this activity book
http://www.amazon.co.uk/Summer-Thing...7372994&sr=1-2 (http://www.amazon.co.uk/gp/product/074607669X/ref=as_li_ss_tl?ie=UTF8&tag=childminding-21&linkCode=as2&camp=1634&creative=19450&creativeASIN=074607669X">Summer Things to Make and Do (Usborne Activities)</a><img src="http://www.assoc-amazon.co.uk/e/ir?t=&l=as2&o=2&a=074607669X" width="1" height="1" border="0" alt="" style="border:none !important; margin:0px !important;)
there is also a good series of factual books for little ones on summer ( winter, spring & autumn! LOL!)
http://www.amazon.co.uk/Summer-Read...7372994&sr=1-6 (http://www.amazon.co.uk/gp/product/1844213439/ref=as_li_ss_tl?ie=UTF8&tag=childminding-21&linkCode=as2&camp=1634&creative=19450&creativeASIN=1844213439">Summer (Read & Learn: Seasons)</a><img src="http://www.assoc-amazon.co.uk/e/ir?t=&l=as2&o=2&a=1844213439" width="1" height="1" border="0" alt="" style="border:none !important; margin:0px !important;)
i also have some story books talking about summer/taking place in summer.
i usually go to amazon (through the forum), put in the theme and see what comes up!