While studying fractions, my class had managed to find 1/2 or 1/6 etc of a quantity on paper indoors but started struggling with finding 4/5 or 2/20 etc. Some of their answers were so way off it showed me that some pupils really didn't understand the concept and some were just following the instructions to divide by the denominator then multiply by the numerator. Some pupils had answers larger than the total quantity and couldn't understand why this was wrong...so back to practical equipment...and outdoors...
I set up a team race activity in the playground. Each team were seated in a huddle so they could discuss the maths involved and 2 pupils per team were selected to race together each time again allowing discussion. Each team was given a bucket filled with beads (stones would be good too). The buckets were placed some distance away and started with 60 beads in each. I was keen the pupils saw fractions of quantities as something real, instead of just numbers in a textbook or on a page.
The first pair of pupils from each of the 3 teams was asked to collect 2/20 of the beads and the first pair back with the correct number of beads in their collecting jar scored 3 points, 2nd 2 points and 3rd 1 point.
The next pair of pupils were asked to collect 1/6 of the beads remaining in the bucket. One team quickly worked out that if they discussed how many beads were left in the bucket each time it saved their team members from counting them when they got there. This encouraged mental arithmetic
After 8 pairs had gone we were left with one bead in the bucket so we put all 60 back in and started again with different fractions to find.
The feedback from my class was very positive and I could see an improvement with the calculations. Interestingly some of the pupils who were getting full marks in the classroom with these kind of problems, were struggling at first as they hadn't related the questions with actually finding a quantity of objects.
There was certainly a lot of talking about fractions going on and a lot of fun racing eachother.