At the time this was reviewed, there were no available published research studies on Frog Street Threes. Research investigating the curriculum is needed to establish evidence on children's learning outcomes.

Approaches to Learning: Frog Street Threes promotes some research-based teaching practices to support children's approaches to learning. It provides guidance on classroom organization (e.g., predictable daily schedule, games and songs to support transitions) and classroom management (e.g., giving children choices). It also offers several activities and strategies to support children's executive function skills (e.g., inviting children to reflect on the day) and emotional regulation (e.g., identifying emotions, helping children express and release their emotions). However, the curriculum lacks opportunities for child-initiated play, activities based on children's interests, and activities that promote open-ended exploration. Research shows these elements are important for supporting children's attention, persistence, curiosity, and creativity.

Social and Emotional Development: Frog Street Threes consistently promotes research-based teaching practices in this domain. It includes guidance on establishing an emotionally supportive environment. For example, the curriculum's "Conscious Discipline" daily routines (e.g., Greeting Circle) and aspects of the physical space (e.g., Kindness Tree, Cool-Off Center) help children feel welcome each day. They also provide spaces for children to express their emotions and ideas. Children are offered opportunities to practice social interaction and relationship skills with their teachers and peers (e.g., partner activities, large and small group activities) within the daily routines and activities described in the Teaching Guides. 

Language and Communication: Frog Street Threes consistently promotes research-based teaching practices to support children's language and communication, such as offering learning opportunities with rich oral language. The daily activities and practice centers described in the Teaching Guides provide children with a variety of formal and informal opportunities to engage in language and communication with adults and peers. Additionally, the Teaching Guides offer research-based strategies to engage children during read-alouds. The curriculum provides guidance for teachers to use and model rich, complex language (e.g., defining terms, describing stories and experiments, asking questions). While the curriculum activities make some connections to children's lives (e.g., inviting children to share about a time they visited the zoo), the activities and practice centers are all prescribed and based primarily on the themes.

Literacy: The curriculum consistently promotes research-based teaching practices to support children's literacy. The Teaching Guides offer strategies to support literacy skills during daily read-alouds, such as asking questions, connecting the story to children's lives, and retelling to aid comprehension. The morning message integrates additional practices, such as modeling writing, examining concepts about print, and building alphabet knowledge. Less research-based guidance is included on how to support children's pre-writing skills and emergent mark-making. 

Mathematics Development: Frog Street Threes promotes some research-based practices in this domain. It includes daily math learning activities and hands-on practice centers. The curriculum provides detailed guidance on how to introduce children to key mathematical concepts and related vocabulary through manipulatives, photos, and stories. It also includes multiple and related opportunities to explore a mathematical concept or skill over time. However, the order of the activities does not always follow children's developmental progressions. The curriculum offers limited opportunities for children to explore math through inquiry and creative invention.

Scientific Reasoning: The curriculum provides some research-based teaching practices to support scientific reasoning. For example, it offers hands-on science experiences that facilitate the development of inquiry skills, such as making observations, asking questions, and gathering information. Science is well-integrated with other domains, such as math, language, and literacy. However, the science activities are prescribed and teacher-directed. There is little room for teachers to build on children's previous experiences and interests or to facilitate open-ended investigation. In addition, some of the activities do not focus on developmentally appropriate content that would allow children to engage in meaningful hands-on exploration (e.g., density of saltwater, gravity, glycerin bubbles).

Perceptual, Motor, and Physical Development: Frog Street Threes includes some research-based teaching practices to support children's perceptual, motor, and physical development. It provides many opportunities to practice new physical skills and activities that introduce children to a broad range of health and safety topics. The Teaching Guides include several "Moving and Learning" activities and practice centers that promote children's perceptual and fine- and gross-motor development. There is less guidance for teachers on how to intentionally scaffold children's physical and self-care skills, as well as their individual temperaments, interests, and cultures in physical activities. The curriculum also lacks guidance around setting up indoor and outdoor environments that promote active physical play.

Scope: Frog Street Threes clearly identifies five developmental domains: Approaches to Learning, Social and Emotional Development, Language, Cognition, and Physical Development. Each Teaching Guide provides detailed guidance for daily learning activities and practice centers to support children's development in these domains.

Sequence: The curriculum offers a sequence of learning experiences to support children's developmental progressions in the following domains: Approaches to Learning, Language and Communication, and Scientific Reasoning. Some aspects of the following domains do not follow children's developmental progressions or lack multiple related opportunities for children to explore skills and concepts over time: Social and Emotional Development, Literacy, Mathematics, and Perceptual, Motor, and Physical Development. For example, "Numeration" is not introduced until Mathematics themes 8 and 9, after "One-to-One Correspondence" is addressed in themes 5 and 6. In a one week period, children are introduced to counting, learning numerals, and understanding cardinality. They reflect skills children would develop over a longer period of time and could be supported much earlier in the program year. In the Literacy domain, the curriculum includes daily activities for children to practice phonological awareness in a whole group context. This is too heavy an emphasis for 3-year-old children. For example, Teaching Guides 1–3 invite children to practice sentence and syllable segmentation by tapping their knees for each word or syllable, which the ELOF shows as a skill for children ages 48–60 months.

Alignment with the ELOF: A thorough review of all curriculum materials in relation to the ELOF domains and sub-domains indicates that Frog Street Threes is mostly aligned with the ELOF. The learning experiences described in the Teaching Guides support children across the majority of ELOF sub-domains and goals. The practice centers (e.g., Writer's Corner, Math, and Creativity Station) also provide opportunities for children to practice domain-specific skills. The curriculum partially addresses the following ELOF sub-domains: Initiative and Curiosity, Creativity, and Sense of Identity and Belonging.

Learning Goals: The Assessment and Planning CD specifies "Frog Street Threes Learning Outcomes," which are measurable and developmentally appropriate learning goals. They are the same goals included in the ELOF. All activities and practice centers in the Teaching Guides specify the learning outcomes. Overall, the learning activities support children in making progress toward learning goals. The Welcome to Frog Street Threes introductory guide provides some information on differentiated instruction, such as adjusting expectations, modifying instruction, and allowing children to participate in various ways. This guidance supports teachers in individualizing learning goals and allowing children to take different paths to reach learning goals.

Ongoing Observation and Documentation: Welcome to Frog Street Threes describes how ongoing assessment is a process used to understand children's current abilities. It helps staff plan individualized activities, note developmental progress or concerns, and guide instruction. It also discusses the process of documenting observations in individual portfolios (e.g., work samples, photographs, information from families, videos). The Assessment and Planning CD includes two anecdotal observation records tools to support teachers in this process. Finally, the curriculum embeds specific guidance on ongoing assessment throughout the Teaching Guides. At the end of each week, there is an "Assessment" section that prompts teachers to assess children on specific skills and concepts related to the week's learning experiences and goals.

Standardized and Structured Assessment Instruments: Frog Street Threes describes and provides a structured assessment tool. Frog Street Threes Developmental Checklist aligns with the curriculum's learning goals. The curriculum encourages programs to complete this assessment tool many times throughout the year, but there is no evidence that establishes the validity and reliability of the tool.

Communicating with Families: Welcome to Frog Street Threes offers some strategies for two-way communication with families (e.g., teachers informing families of program policy, families informing teachers about what happens over the weekend). The Family Connections CD provides a range of materials for sharing information with families, such as letters about the curriculum's learning experiences. It also includes an "All About Me" form to learn from families about children's development and routines at home. While the materials for families are translated into Spanish, there are no further resources or specific guidance on how to communicate with families in culturally and linguistically responsive ways.

Engaging Families: The curriculum provides multiple resources to support parent and family engagement in their children's learning and development. For example, the Parents Are Teachers Too (PATT) Mats are hands-on, open-ended activities for families to do at home with their children. They are available in both English and Spanish. The curriculum also provides "Family Connection" cards with strategies and activities for families to engage in with their children (e.g., encouraging children to notice numerals in the environment, supporting children to plan and build a structure with blocks, boxes, or pillows). While the parent and family engagement resources are plentiful, there is limited consideration for how to engage families from diverse cultures, families who speak languages other than English or Spanish, or families with disabilities and other special needs.

Professional Development: Frog Street Threes offers in-person courses for standardized initial and ongoing training at an additional cost (e.g., Frog Street Threes Curriculum Implementation, Frog Street Threes Curriculum Follow-Up). The courses can be half- or full-day. Training topics include scope and sequence for math and literacy; science, technology, engineering, arts, and math (STEAM) activities; and family engagement. The publisher also offers train-the-trainer opportunities and one-on-one training that can be customized to meet the needs of programs (e.g., discussing challenges and areas of growth, providing classroom observations based on needs).

Curriculum Materials to Support Implementation: Frog Street Threes includes a comprehensive set of materials to support implementation. The Welcome to Frog Street Threes introductory guide provides an overview of the curriculum materials, such as the Teaching Guides, CDs, manipulatives, and books for children. It includes information on setting up the learning environment and designing learning centers. The Teaching Guides provide daily lesson plans for each theme and describe the content and strategies for implementation (e.g., goals for the activities, questions to ask, and scaffolding strategies).

• Fidelity Tool: The curriculum's Administrator Classroom Observation Tool can be used to monitor quality or assess the fidelity of implementation. It guides observation in different areas, such as the teacher's sensitivity to social and emotional needs, instructional strategies implemented in small and large groups, the classroom environment, and learning centers.

Active Exploration: Welcome to Frog Street Threes discusses the importance of hands-on activities and open-ended exploration. Some of the suggested practice centers and activities in the Teaching Guides allow children to actively explore their environment in open-ended ways. For example, children have opportunities to build block towers or a robot out of recycled materials. However, many of the activities are more teacher-directed. Children are invited to do something very specific, with limited opportunity to engage with the environment in open-ended ways. Several activities have children roll playdough into "monkey tails" and place them over numerals. In another activity, teachers model how to make a paper plate puppet and children are directed to do the same thing.

Interactions That Extend Children's Learning: Many of the curriculum's resources provide guidance and examples on how to extend children's learning. For example, Welcome to Frog Street Threes offers prompts to encourage children's curiosity (e.g., What do you notice about…? What do you think will happen if …?). "Photo Activity Cards" provide examples of different types of questions and prompts to extend children's thinking and communication (e.g., What are other objects with a similar shape? What bumps do you feel?). Many learning activities and practice centers provide prompts to extend children's exploration, thinking, and communication (e.g., math and science activities include prompts for children to predict, hypothesize, test, and reason; closing circle activities ask children to reflect on the day).

Individualization: The curriculum provides specific guidance on how to individualize learning experiences for all children. Many of the literacy, math, and science activities provide "Special Needs Adaptations" to include children with disabilities and other special needs. In addition, some learning experiences offer scaffolding strategies to support children who are DLLs. Only a few learning experiences throughout the curriculum prompt teachers to consider children's cultures throughout learning activities.

Environment: Welcome to Frog Street provides general principles and tips for setting up the physical space and practice centers, including adequate space, safety, and open-ended exploration. The practice centers provide some guidance on environmental setup to support children's development in the ELOF domains. While the suggested daily schedule calls for outdoor learning, the curriculum lacks adequate direction on how to set up the outdoor environment; only some weeks provide an "Outdoors" practice center. There is some guidance for how to provide environmental supports for children with disabilities or other special needs, but minimal information on how to authentically integrate children's cultures and home languages into the learning environment.

Learning Materials: Frog Street Threes provides developmentally appropriate learning materials, such as books, music CDs, math manipulatives, and sequence cards. The Teaching Guides offer suggestions for using learning materials (e.g., blocks, playdough, recycled materials, materials from nature, scientific tools) in specific activities and practice centers. The curriculum provides some guidance for ensuring the learning materials meet the unique needs of children with disabilities and other special needs. It also includes a couple examples of how to select learning materials that authentically represent the cultures and ethnicities of children in the program.

Schedule and Routines: Welcome to Frog Street Threes describes the various parts of a typical day: greeting circle, morning message, read-aloud times, moving and learning, STEAM lessons, math and literacy practice centers, and closing circle. It offers specific examples of half- and full-day schedules. However, the entire day is prescribed with routines and small and whole group activities, with little room for child-directed free play. The organization of the Teaching Guides reiterates the suggested schedule. Aside from tips on transitions, the curriculum lacks guidance on how to establish and support children's learning during developmentally appropriate daily routines (e.g., rest time, lunch). It offers a few examples of how to adjust schedules and routines based on children's needs (e.g., incorporating massage, connection rituals, and visual routines for children who are biting).

Interactions: Welcome to Frog Street Threes includes a brief section on "Cultural Sensitivity." There are very few tips that could be used to build relationships with children and families from diverse cultural backgrounds (e.g., treating people as individuals rather than as stereotypes, focusing on similarities and differences without making judgments, modeling respect for others). The Teaching Guides very rarely mention the importance of culturally responsive interactions (e.g., discussing manners in other cultures). When they do, there is no additional specific guidance or strategies provided on how to engage in culturally responsive interactions with diverse children and families. 

Learning Experiences: In their "Dual Language Learners" prompts, the curriculum includes a few brief examples of providing learning experiences that build on families' cultures. One activity invites families to bring fruits and vegetables from their cultures; another suggests families from other countries share folktales, etiquette, and manners that are common in their cultures. There is also an activity that reminds teachers to be mindful of different cultures and customs represented in the classroom when discussing what children know about cowboys. The curriculum lacks further specific guidance embedded in the Teaching Guides on how to engage children in learning experiences that build on families' traditions, cultures, values, and beliefs.

Learning Environment: Frog Street Threes offers two suggestions for providing learning materials that reflect children and families from diverse cultures and ethnicities. It recommends presenting a variety of foods for snack and lunch and using books, photographs, and posters that celebrate a wide variety of ethnic groups. Additionally, the curriculum's "Literature Library," "Photo Activity Cards," and "Vocabulary Cards" include books and photos representing children and families from diverse cultures and ethnicities. However, some images in the "Sing & Read Alphabet eStories" provide a stereotypical rather than an authentic representation of diverse people (e.g., the letter "E" e-book uses the term "Eskimos," who are depicted in parkas alongside elks; the letter "I" e-book illustrates "Indians" with feathers in their hair). In addition, the curriculum lacks guidance on how to select and use learning materials that authentically represent the cultures and ethnicities of children and families in the program. 

Scaffolding Strategies: The curriculum provides specific guidance on scaffolding the development and learning of children who are DLLs. Welcome to Frog Street Threes provides a range of teaching practices to support children who are DLLs (e.g., adding pictures of words to story vocabulary lists, dramatizing to support vocabulary acquisition). Specific scaffolding strategies are embedded throughout the learning activities in the Teaching Guides (e.g., pairing children at different levels of language acquisition together, discussing cognates, and highlighting similarities in vocabulary words).

Home and Tribal Languages: Welcome to Frog Street Threes mentions the importance of supporting children's home languages but provides no specific suggestions or guidance for how to meaningfully integrate home or tribal languages into the classroom. Across the curriculum, only two examples of integrating home languages in the classroom were cited: encouraging children to share words used in their native languages to represent noises, and inviting children to teach their peers how to count in their home language. The curriculum lacks guidance on other research-based strategies to support children's home languages, such as learning and using words and phrases in a home or tribal language, providing directions in a language children understand, and including learning experiences in a home or tribal language. Tribal languages are not addressed.

Teaching Practices and Interventions: Welcome to Frog Street Threes provides general guidance for working with children with special needs (e.g., planning activities that include all children, working with the child's family). It also includes descriptions and adaptations to support children with specific disabilities or special needs (e.g., allowing children with visual impairments to explore things through touch and sound). The Teaching Guides provide specific modifications to ensure daily routines and activities are inclusive of children with disabilities and other special needs (e.g., simplifying an activity, inviting children in wheelchairs to participate in a movement activity using different body parts).

Learning Environment: The curriculum provides guidance on how to ensure the physical environment and learning materials are accessible to children with disabilities and other special needs. For example, Welcome to Frog Street Threes includes strategies like adjusting the lighting and using simple adaptive devices. Similarly, the Teaching Guides occasionally offer suggestions for additional learning materials to support children with disabilities and other special needs (e.g., give children a larger tool than an eyedropper, adapt a ball-catching activity by letting children use a net or bucket).

Individualization Based on Interests: Welcome to Frog Street Threes discusses the importance of following children's interests (e.g., invite children to choose books; if a child shows an interest in bugs, take them outside to search for crawling critters). Occasionally, the curriculum's learning activities or practice centers invite children to share their curiosities and wonderings. However, the curriculum does not offer guidance on how to plan learning experiences that build on individual children's interests. Learning experiences are preplanned and there is no guidance on how to modify them based on individual children's interests.

Individualization Based on Strengths and Needs: The curriculum provides a variety of strategies to make learning experiences responsive to individual children's strengths and needs. For example, Welcome to Frog Street Threes describes the importance of differentiated instruction and some high-level strategies to promote it. The Teaching Guides offer specific suggestions for modifying learning experiences for children with disabilities and other special needs, as well as children who are DLLs.