Identify and order Roman numerals

Game: Estimate angles to reflect lines

Game: Strategize to solve logic problems (partition squares)

Game: Strategize to solve logic problems (lights)

Game: Strategize to solve logic problems (river)

Create sums with same factor

Create equal sums with multiples of 10 (known sum)

Divide whole numbers

Create equal sums (known sum)

Strategize to solve subtraction problems (fractions, unlike denominators)

Solve problems with addition and multiplication (six options)

Create equal sums (known sum)

Strategize to solve subtraction problems (fractions, like denominators)

Add Roman numerals

Create equal sums (known sum)

Strategize to solve subtraction problems (fractions, related denominators)

Create equal sums with multiples of 10 (unknown sum)

Strategize to solve subtraction problems (three terms, three operations)

Create equal sums (unknown sum)

Create equal sums (unknown sum)

Create equal sums (unknown sum)

Riddle: Find all factor pairs (rectangle, grid)

Riddle: Model with algebra (siblings)

Riddle: Count combinations (matching socks)

Riddle: Count combinations (flowers)

Riddle: Use backtracking to find a number (four operations)

Riddle: Balance two products (crab and coin)

Riddle: Find the lowest common multiple (beads)

Riddle: Find the secret number (addition, multiplication)

Riddle: Find the largest product (digits)

Riddle: Model with algebra (addition, subtraction, multiplication)

Riddle: Solve logic puzzles (truths and lies)

Riddle: Find the whole from remainders (division)

Riddle: Model with algebra (sibling ages)

Riddle: Plan a trip (fuel)

Riddle: Identify relatively prime numbers (coprime)

Riddle: Solve logic puzzles (truths and lies)

Riddle: Count partitions (chocolate bars)

Riddle: Count combinations (animal heads and legs)

Riddle: Find unknowns with algebra (number replacement)

Riddle: Find the secret number (factors)

Riddle: Count events (band)

Riddle: Find the secret number (divisibility)

Riddle: Model with algebra (ages)

Riddle: Find unknowns with algebra (arithmetic)

Riddle: Solve with percentages (fruit drying)

Riddle: Calculate weights (jam jars)

Game: Strategize to solve logic problems (wigs)

Use process of elimination

Riddle: Solve logic puzzles (combinations, constraints)

Create composite shapes (complex, with rotation)

Riddle: Estimate area (squares, grid)

Riddle: Calculate area (overlapping squares)

Find two numbers that add to 100 (Roman numerals)

Find two numbers that add to 20 (Roman numerals)

Explore our geometric tools

Teacher demonstration: Place value (two digits)

Teacher demonstration: Place value (three digits)

Teacher demonstration: Place value (four digits)

Teacher demonstration: Number line