Probability Experiments
Grade 4 probability formalizes experimental results as fractions: if heads appeared 8 times in 20 flips, the experimental probability is 8/20 = 2/5. This fraction representation bridges informal probability language (more likely, less likely) and the formal probability scale from 0 to 1. First Peoples games of chance demonstrate that probabilistic reasoning is embedded in traditional gaming culture across many nations.
Probability as a fraction
Theoretical probability of rolling a 3 on a standard die: 1 outcome out of 6 possible = 1/6. Theoretical probability of drawing a red marble from a bag of 3 red and 7 blue = 3/10. Experimental probability: actual results as a fraction of total trials. 12 reds in 30 draws = 12/30 = 2/5. Comparing theoretical (3/10) to experimental (2/5=4/10): close but not identical.
Recording with tallies and converting
After 20 coin flips: heads: IIII IIII III (13), tails: IIII II (7). Experimental probability of heads: 13/20. Record in a table: outcome, tally, frequency, fraction. This structured recording builds the data literacy skills needed for statistics in later grades.
First Peoples games of chance
The BC curriculum references Dene/Kaska hand games (guessing which hand holds the marked stick) and Lahal stick games (a guessing game with sticks) as probability contexts. These traditional games encode probabilistic reasoning about opponent strategies and chance. Inviting community members to share these games connects probability to cultural practice.