Just sorting out my DS1's 4th party for next week. my first 'proper' kids party too.
Theme: Tractors - green and yellow balloons, plates, cups etc. tractor cake.
Time: 2 hours
Games: Pin the wheel on the tractor (tail/donkey)
Apple collection race ( brown plastic sheet on floor for mud, paper stepping stones, a pile of green and red ball pool balls on the other side. split the group into 2 teams and race to get all your 'apples' back across the mud.
Musical corners (each corner being a picture of a tractor, one john deere, one massey, one NH and one Kubota (or green, red, blue and orange for the non-tractor mad!).
Food: one plate pre done per child - sandwich, veg sticks, fruit pieces and a small portion of skips/quaver
Party bags: slice of cake, tractor sticker sheet, mini bubbles and a balloon ( the bag totals £1 per child!)
Adults: Help yourself tea and coffee station with biscuits.
Costs: Hall £30, party bags £20, decorations/plates/cups £25, food £15. I make the cake but I think it will be about £40 (but it will be a huge tractor shaped one. Total cost: £130 for 20 kids and their adults, £90 without the extravagant cake, but I do so love making them!
I didn't invite the whole class, he picked 8 friends plus some out of school friends. Sent invites in 2 weeks before the Christmas break up due to early jan birthday. I don't personally feel parties need to be filled with crisps/cake/junk hence no sweets in party bag and only cake as a 'sweet treat' but that is my personal preference.
Hope that helps! and good luck!