Estimation
Recall groupings of twos, threes, fives, and tens that are in numbers to 100 and the resulting remainders.
Number Framework Stage 6
Show the students collections of objects on an overhead projector. Mask the collections initially with a book then uncover them briefly. Encourage strategies like looking for instantly recognisable patterns and using these as a sample with which to estimate the whole collection.
You might also develop sampling by using a frame, like a cut out plastic lid, to isolate part of the collection. For example, 10 objects are inside the frame, that is about one-sixth of the collection, so there are about 60 objects in total in the collection.
Activity
The students at the Advanced Additive thinking stage and onwards should apply multiplicative strategies. Fill clear plastic jars with beads, buttons, or similar objects and get the students to estimate the total number. Encourage strategies like taking a cross section and multiplying that by how many times the cross section will fit into the collection.
Similar Resources
Dividing? Think about Multiplying First
Recall multiplication to 10 x 10, and the corresponding division facts.
Recall groupings of twos, threes, fives, and tens that are in numbers to 100 and the resulting remainders.
Number Boggle
Recall the number of 10s within decades and decades that add to 100.
Recall addition and subtraction facts to 20.
Tens in Hundreds and More
Recall the number of tens and hundreds in 100s and 1000s.
Recall groupings of twos, threes, fives, and tens that are in numbers to 100 and the resulting remainders.
Find out how many ones, tens, hundreds and thousands are in all of a whole number.
Find the number of tenths, hundredths, and one–thousandths in numbers of up to three decimal places.
Zap
Recall the number of 10s within decades and decades that add to 100.
Recall groupings within 100.
Find out how many ones, tens, hundreds and thousands are in all of a whole number.
Know what happens when a number is multiplied or divided by a power of 10.
Traffic Lights
Recall groupings within 100.
Recall groupings within 1000, e.g., 240 + 760.
