Investigations in Number, Data, and Space

Provides extensive teacher guidance with detailed instructional notes. Teachers appreciate the clear instructions and explanations of student thinking patterns.

Teachers appreciate 'clear teacher instructions with extensive notes throughout sessions explaining how children respond and what concepts are being developed'

Strong emphasis on visual models and manipulatives throughout the curriculum. Teachers particularly praise the hands-on geometry activities and visual supports.

Teachers praise visual supports like array cards; geometry work with geoblocks is highlighted; hands-on activities with manipulatives receive particular praise; parents reported as 'amazed by geometry activities'

The curriculum appears to minimize worked examples in favor of student discovery and invention of strategies. This approach may increase cognitive load for novice learners.

Harvard professor Wilfried Schmid argues 'TERC teachers don't explain or teach, reducing mathematics instruction to discovery learning'; the curriculum encourages students to develop their own problem-solving strategies rather than studying model solutions

The curriculum minimizes direct instruction in favor of guided discovery and student-led exploration. This approach conflicts with research on effective mathematics instruction.

Curriculum 'encourages students to develop their own problem-solving strategies'; described as reducing 'mathematics instruction to discovery learning'; teachers guide rather than directly teach computational methods

Uses a spiral approach with instructional units lasting 2-5.5 weeks focusing on particular content areas. The approach may risk insufficient depth in foundational skills.

WWC describes units as focusing on particular content areas for 2-5.5 weeks; critics suggest TERC students may be 'roughly two years behind by fifth grade'

The curriculum strongly emphasizes conceptual understanding but shows weaknesses in procedural fluency development. While the 2007 revision increased attention to basic skills, critics note students may lag in standard computational methods.

EdReports rated it 'Does Not Meet Expectations' for alignment; critics note TERC's nonstandard computational methods substitute for standard methods needed for algebra; however, teachers report students develop efficient alternative computing strategies

Emphasizes meaningful mathematics problems with multiple entry points. However, systematic instruction in problem-solving schemas may be limited.

Program emphasizes 'meaningful mathematics problems with multiple entry points to accommodate the full range of student abilities'; sessions include 'hands-on math activities' and problem solving

Limited evidence of systematic retrieval practice and spaced review components. The focus on discovery learning may not adequately address skill retention needs.

No specific mentions of retrieval practice, cumulative review, or spaced practice in the available reviews; emphasis appears to be on ongoing exploration rather than systematic review

Sessions include assessment activities, though the extent and effectiveness of diagnostic capabilities is unclear from available evidence.

WWC notes that sessions include 'assessment activities' along with hands-on activities and discussions, but limited detail on diagnostic assessment features